Comparison Lenovo K6 Power Dual 16 GB / 2 GB vs Lenovo K6 Power 16 GB / 2 GB

Characteristics of the main (and most often the only) display installed in the device.

In addition to the basic properties - such as size, resolution (according to it, screens are conventionally divided into HD, Full HD, 2K and more), sensor type (most often IPS, OLED, AMOLED, Super AMOLED, Dynamic AMOLED,), this list can more specific features. Among them are the shape of the surface ( flat or curved), the presence and version of the Gorilla Glass coating (including the top v6 and Victus), HDR support and the refresh rate (a frequency on top 60 Hz is considered high, namely 90 Hz, 120 Hz and 144 Hz) . Here is a more detailed description of the characteristics relevant to modern displays:

- Size. Traditionally, the screen size is indicated in inches. A larger display is more convenient to use: more information is placed on i...t, and the image itself is better readable. The downside of increasing the size is an increase in the dimensions of the device. Today, smartphones with screens of 5" or less are considered small. 5.6 - 6" and up to 6.5" is already a medium format. Also, many modern models have a size of 6.5". Classic phones without touch screens do not need a large size - in them it usually does not exceed 3".

- Permission. Screen resolution is specified based on its vertical and horizontal dimensions in dots (pixels). The larger these dimensions (with the same size) - the more detailed and smoothed the picture looks and the less individual pixels are visible on it. On the other hand, increasing the resolution increases both the cost of the display itself and the requirements for the phone's hardware. It is also worth noting that the same resolution on screens of different sizes looks different; so when evaluating detail, it is worth considering not only this parameter, but also the PPI number (see below).

— PPI. The density of dots (pixels) on the screen of the device. It is indicated by the number of dots per " (points per ") - the number of pixels for each horizontal or vertical segment of 1 ". This indicator depends both on the size and resolution, but in the end it is the PPI number that determines how smooth and detailed the image on the display is. For comparison, we note that at a distance of about 25 - 30 cm from the eyes, a density of 300 PPI or more makes individual pixels almost invisible to a person with normal vision, the picture is perceived as a complete one; at greater distances, a similar effect is noticeable at a lower point density.

— Matrix type. The technology by which the screen sensor is made. This parameter is indicated only for relatively advanced displays that are superior in performance to the simplest LCD screens of push-button phones. The most widespread in our time are the following types of matrices:

• IPS. The most popular technology for the screens of modern smartphones. It provides a very decent image quality, viewing angles and response speed, although it is somewhat inferior in these parameters to many more advanced options (see below). On the other hand, IPS also has important advantages: durability, uniform wear, and also a rather low cost. Thanks to this, such screens can be found in all categories of smartphones - from low-cost to top-end.
• AMOLED. Organic light-emitting diode (OLED) sensor technology developed by Samsung. One of the key differences between such matrices and more traditional displays is that they do not require external illumination: each pixel is its own light source. Because of this, the power consumption of such a screen depends on the characteristics of the displayed image, but in general it turns out to be quite low. In addition, AMOLED matrices are distinguished by wide viewing angles, excellent brightness and contrast ratios, high color reproduction quality and fast response time. Due to this, such screens continue to be used in modern smartphones, despite the emergence of more advanced technologies; they can be found even in top-end models. The main disadvantage of this technology is the relatively high cost and uneven wear of the pixels: dots that work longer and more often at high brightness burn out faster. However, usually this effect becomes noticeable only after several years of intensive use - a period comparable to the operational resource of the smartphone itself.
• AMOLED (LTPO). An advanced version of AMOLED panels with the ability to dynamically adjust the refresh rate depending on the tasks performed. The abbreviation LTPO stands for Low Temperature Polycrystalline Oxide. Behind this term is a combination of traditional LTPS technology and a thin layer of TFT oxide film with the addition of hybrid-oxide polycrystalline silicon to drive the sweep switching circuits. AMOLED panels (LTPO) reduce the energy consumption of the gadget by an order of magnitude. So, when performing active actions, the device screen uses the maximum or high refresh rate, and while viewing pictures or reading text, the display reduces the rate to a minimum.
• Super AMOLED. An improved version of the AMOLED technology described on top One of the key improvements is that in Super AMOLED screens there is no air gap between the touch layer and the display located under it. This made it possible to further increase the brightness and image quality, increase the speed and reliability of the sensor response and at the same time reduce power consumption. The disadvantages of such matrices are the same as the original AMOLED. In general, they are quite widespread; most smartphones with similar screens belong to the middle and top categories, but there are also low-cost models.
• OLED. Various types of matrices based on the use of organic light emitting diodes; in fact - analogues of AMOLED and Super AMOLED, produced not by Samsung, but by other companies. The specific features of such screens may be different, but for the most part they are, on the one hand, more expensive than popular IPS, on the other hand, they provide higher image quality (including brightness, contrast, viewing angles and color fidelity), and also consume less energy and have small thickness. The main disadvantages of OLED screens are the high price (which, however, is constantly decreasing as the technology develops and improves), as well as the susceptibility of organic pixels to burn-in when broadcasting static images for a long time or images with static elements (notification panel, on-screen buttons, etc.). ).
• OLED (polymer). Organic Light-Emitting Diode (OLED) screens, which do not use glass as a base, but a transparent polymer material. We emphasize that we are talking about the basis of the sensor; from on top it is covered with the same glass as in other types of screens. However, this design offers a number of advantages over traditional "glass" matrices: it provides additional impact resistance and is great for creating curved displays. On the other hand, in terms of optical properties, plastic still falls short of glass; so screens of this type are often inferior in image quality to their “peers” made using traditional OLED technology, and with a similar picture quality, they are noticeably more expensive.
• OLED (LTPO). OLED-matrices with adaptive refresh rate, which can be changed in a wide range based on the tasks performed. In games, screens with LTPO technology automatically raise the refresh rate to the maximum values, while viewing static images, they reduce it to a minimum (from 1 Hz). At the heart of the technology is a traditional LTPS substrate with a thin TFT oxide film on top of the TFT base. The ability to control the flow of electrons provides dynamic control over the refresh rate. The competitive advantage of OLED (LTPO) is reduced power consumption.

In addition, screens in modern smartphones can be made using the following technologies:

• pls. A variation of IPS technology created by Samsung. In some respects - in particular, brightness, contrast and viewing angles - it surpasses the original, while it is cheaper to manufacture and allows you to create flexible displays. However, for a number of reasons, it is not particularly popular.
• Super AMOLED Plus. A further development of the Super AMOLED technology described on top. Allows you to create even brighter, more contrasting and at the same time thin and energy-efficient screens. However, most often such screens in our time are simply referred to as "Super AMOLED", without the "Plus" prefix.
• Dynamic AMOLED. Another AMOLED improvement introduced in 2019. The main features of such matrices are increased brightness without a significant increase in power consumption, as well as 100% coverage of the DCI-P3 color space and compatibility with HDR10 +; the last two points, in particular, make it possible to reproduce modern high-low-cost cinema on such screens with the highest quality. The main disadvantage of Dynamic AMOLED is traditional - the high price; so such matrices are found mainly in top models.
• Super Clear TFT. A joint development by Samsung and Sony, which appeared as a forced alternative to Super AMOLED matrices (the demand for them at one time significantly exceeded production capabilities). True, the image quality of Super Clear TFT is somewhat lower - but in production such matrices are noticeably simpler and cheaper, but in terms of performance they still surpass most IPS screens. However, in our time, this technology is rare, giving way to AMOLED in different versions.
• super LCD. Another alternative to various kinds of AMOLED technology; used mainly in HTC smartphones. Similar to Super AMOLED, such screens do not have an extra air gap, which has a positive effect on both image quality and the clarity of sensor responses. A notable advantage of the Super LCD is its good power efficiency, especially when displaying bright whites; but in terms of overall color saturation (including black), this technology is noticeably inferior to AMOLED.
• LTPS. An advanced type of TFT matrices, created on the basis of the so-called. low temperature polycrystalline silicon. It allows you to easily create screens with a very high pixel density (more than 500 PPI - see on top), achieving high resolutions even with a small size. In addition, part of the control electronics can be built directly into the sensor, reducing the overall thickness of the display. The main disadvantage of LTPS is the relatively high cost, but nowadays such screens can be found even in low-cost smartphones.
• S-PureLED. A technology developed by Sharp and used primarily in its smartphones. Actually, the technology of the matrices themselves in this case is called S-CG Silicon TFT, and S-PureLED is the name of a special layer used to increase transparency. S-CG Silicon TFT is positioned by the creators as a modification of the LTPS technology described on top, which allows to further increase the resolution of the display and at the same time build more control electronics into it (up to a whole “processor on glass”) without increasing the thickness. Of course, these screens are not cheap.
• e-ink. Matrices based on the so-called "electronic ink" - a technology common primarily in electronic books. The main feature of such a screen is that during its operation, energy is spent only on changing the image; a still picture does not require power and can remain on the display even in the absence of power. In addition, by default, E-Ink matrices do not glow on their own, but reflect outside light - so their own backlight is not necessary for them (although it can be provided for work at dusk and darkness). All this provides a solid energy savings; and for some users, such screens are purely subjectively more comfortable and less tiring than traditional matrices. On the other hand, E-Ink technology also has serious drawbacks - first of all, a long response time, as well as the complexity and high cost of color displays, combined with poor color reproduction quality on them. In light of this, in smartphones, such matrices are a very rare and exotic option.

— Sweep frequency. The maximum display refresh rate, in other words, the highest frame rate that it can effectively reproduce. The higher this figure, the smoother and smoother the image is, the less noticeable the “slideshow effect” and blurring of objects when moving on the screen. At the same time, it should be borne in mind that the refresh rate of 60 Hz, supported by almost any modern smartphone, is quite sufficient for most tasks; even high-definition videos hardly make use of high frame rates these days. Therefore, the scanning frequency in our catalog is specially specified mainly for screens capable of delivering more than 60 Hz (in some models - up to 240 Hz). Such a high frequency can be useful in games and some other tasks, it also improves the overall experience of the OS interface and applications - moving elements in such interfaces move as smoothly as possible and without blurring.

HDR. A technology that allows you to expand the dynamic range of the screen. In this case, the range of brightness is implied - simply put, the presence of HDR allows the screen to display brighter whites and darker blacks than on displays without support for this technology. In practice, this gives a noticeable improvement in image quality: the saturation and reliability of the transmission of various colors improves, and the details in very light or very dark areas of the frame do not “sink” in white or black. However, all these advantages become noticeable only on the condition that the content being played is originally recorded in HDR. Nowadays, several varieties of this technology are used, here are their features:

• HDR10. Historically the first of the consumer HDR formats, it is extremely popular today: in particular, it is supported by almost all streaming services with HDR content and is standardly used for such content on Blu-ray discs. Provides a color depth of 10 bits (more than a billion shades). At the same time, HDR10+ format content (see below) can also be played on devices with this technology, except that its quality will be limited by the capabilities of the original HDR10.
• HDR10+. An improved version of HDR10. With the same color depth (10 bits), it uses the so-called dynamic metadata, which allows transmitting information about the color depth not only for groups of several frames, but also for individual frames. This results in an additional improvement in color reproduction.
• Dolby vision. An advanced standard used particularly in professional cinematography. It allows you to achieve a color depth of 12 bits (almost 69 billion shades), uses the dynamic metadata mentioned on top, and also makes it possible to transmit two image options at once in one video stream - HDR and normal (SDR). At the same time, Dolby Vision is based on the same technology as HDR10, so in modern electronics this format is often combined with HDR10 or HDR10 +.

- DC Dimming support. Literally from English, Direct Current Dimming is translated as direct current dimming. This technology is designed to minimize flicker in OLED and AMOLED screens, which, in turn, reduces the load on the user's visual apparatus and protects eyesight. The “flicker-free” effect is achieved by directly controlling the brightness of the backlight LEDs by changing the voltage applied to them. Due to this, a decrease in the intensity of the glow of the screen is ensured.

- Curved screen. A screen that has curved edges to which the displayed image extends. In other words, in this case, not only glass is curved, but also part of the active sensor. Displays where both edges are curved are sometimes referred to as "2.5D glass" as well; also there are devices where the screen is bent only on one side. In any case, this feature gives the smartphone an interesting appearance and improves the visibility of the image from some angles, but it significantly affects the cost and can create inconvenience when holding (especially without a case). So before buying a model with such equipment, ideally, you should hold the device in your hand and make sure that it is comfortable enough.

- Gorilla Glass. Special high-strength glass used as a display cover. It is characterized by endurance and resistance to scratches, many times superior to ordinary glass in these indicators. It is widely used in smartphones, where large screen sizes put forward increased requirements for coverage reliability. Modern phones may have different versions of this glass, here are the features of different options:

• Gorilla Glass v3. The oldest of the current versions is released in 2013; now found mainly among inexpensive or obsolete devices. However, this coating also has undoubted advantages: this is the first generation of Gorilla Glass, where the creators have made a noticeable emphasis on resistance to scratches from keys, coins and other objects that the phone can “collide” in a pocket or bag. In this respect, the v3 version remained unsurpassed until the release of Gorilla Glass Victus in 2020.
• Gorilla Glass v4. Version released in 2014. A key feature was that the development of this coating focused on impact resistance (whereas previous generations focused mainly on scratch resistance). As a result, the glass is twice as strong as in version 3, despite the fact that its thickness is only 0.4 mm. But here's the scratch resistance, compared with its predecessor, has decreased slightly.
• Gorilla Glass v5. A gorilla improvement released in 2016 to further improve impact resistance. According to the developers, the glass of the v5 version is 1.8 times stronger than its predecessor, remaining intact in 80% of drops from a height of 1.6 m "face down" on a rough surface (and guaranteed impact resistance is 1.2 m). Scratch resistance has also improved somewhat, but this material still falls short of v3 performance.
• Gorilla Glass v6. Version introduced in 2018. For this coating, a 2-fold increase in strength compared to its predecessors is claimed, as well as the ability to endure multiple drops on a hard surface (in tests, v6 glass successfully endured 15 drops from a height of 1 m). The maximum drop height (single) with guaranteed integrity is declared at 1.6 m. Scratch resistance has received practically no improvement.
• Gorilla Glass 7. Original name for Gorilla Glass Victus - see below.
• Gorilla Glass Victus. The "heir" of Gorilla Glass 6, released in the summer of 2020. In this coating, the creators paid attention not only to increasing the overall strength, but also to improving scratch resistance. According to the latter indicator, Victus surpasses even the v3 version, not to mention more sensitive materials (and compared to v6, scratch resistance is claimed to be twice as high). As for durability, it allows you to guarantee to endure single drops from a height of up to 2 m, as well as up to 20 consecutive drops from a height of 1 m.

The ratio of the screen area to the total front panel area of the phone. Simply put, this spec describes how much of the front panel is occupied by the screen; the rest is the bezels.

This indicator is given exclusively for smartphones with touch screens — it is for them that it is most relevant. The larger the percentage of the body is occupied by the screen, the thinner are the bezels, the neater the smartphone looks and the more convenient it is to work with it with one hand. As for specific numbers, the average values are 80 – 85 %, the higher values allow us to talk about a thin bezel, and more than 90 % — about a “bezel less” design.

Separately, we note that this parameter has nothing to do with the aspect ratio of the screen. The aspect ratio describes only the display itself — its proportions, the ratio between the larger and smaller side of the rectangle.

The type of SIM card used in the mobile phone. The term SIM here means all types of cards for identification in mobile networks, including 3G networks, CDMA, etc. (although formally such cards may have other names). The type of such a card is primarily described by its form factor. Here are the most common options:

— micro SIM. The largest type of sim cards widely used in modern devices: its' size is 15x12 mm. It was introduced back in 2010, nowadays it is being replaced by more compact and advanced nano-SIM and eSIM. Keep in mind that a microSIM card can be made by simply cutting a larger mini-SIM to the dimensions mentioned above. However this is associated with a certain risk and requires accuracy, so it is better to contact your mobile carrier to replace the SIM card with a suitable one.

— Nano-SIM. The smallest form factor of classic (replaceable) SIM-cards is 12x9 mm. In such cards the frames are cut off almost to the very chip. This standard appeared back in 2012, but it is still extremely common. Like microSIM, a card for a slot of this format can be made by cutting a larger SIM card, but this requires extreme accuracy and is not recommended.

— e-SIM. This type of SIM card is an electronic module that is built directly into the device and cannot be replaced. To authorize in the network of a mobile carrier, you need to make the appropriate settings in the eSIM. Those m...odules are able to save several sets of settings at once, which makes it easy to switch between different carriers — no need to bother with the physical replacement of the SIM card, just change the profile in the settings. Another advantage of such modules is compactness. However, before buying a phone with an eSIM, you should clarify whether this technology is supported by your mobile carrier — even nowadays, not every network is compatible with such modules.

— nano+eSIM. An option found in smartphones with two SIM cards. The built-in eSIM module in such a device is complemented by a slot for a replaceable nanoSIM card. The features of each of these card types are detailed above. It is convenient to keep the main phone number (s) on eSIM, and use replacement cards for temporary numbers. Such scenario may come in handy if you travel abroad a lot — you can install cards from local carriers in the traditional nanoSIM slot.

The quantity and types of removable cards (SIM, memory cards) that can be installed in the phone. On E-Catalog this parameter is specified only for devices that allow the installation of more than one SIM card — most often that means 2 SIM cards, however, you can find devices with three or even four corresponding slots.

Initially several slots mean that several phone numbers can be used on one device. Thus it is possible to combine personal and work numbers, separate plans for calls and the Internet, etc. in one device. However modern devices (especially smartphones) often provide the combined design “SIM + SIM / memory card " : one of the slots is intended only for SIM, the second can be used both for a SIM card or for a memory card such as microSD or Nano Memory (see "Memory card slot"). At the same time, there is no separate slot for a memory card in the device, so the user has to choose between the second number and additional storage. Therefore, if you want to use 2 SIM cards and a memory card at the same time, you should pay attention to models where this is directly stated.

It is also worth considering that individual slots may differ in the type of compatible SIM cards; see below for details.

Types of communications supported by the device in addition to mobile networks.

This list includes two types of characteristics. The first is the communication technology itself: Wi-Fi (including advanced standards Wi-Fi 5 (802.11ac) , Wi-Fi 6 (802.11ax), Wi-Fi 6E (802.11ax) , Wi-Fi 7 (802.11be)), Bluetooth (including the new generation Bluetooth v 5 in the form of a version 5.0, 5.1, 5.2, 5.3 and 5.4), NFC, satellite communication. The second type is additional functions implemented through one or another communication standard: this is primarily aptX support (including aptX HD, aptX Adaptive and aptX Lossless) and even a built-in walkie-talkie. Here is a more detailed description of each of these characteristics:

— Wi-Fi 4 (802.11n). Wi-Fi is a wireless communication technology that in modern phones can be used both to access the Internet through wireless access points, and for direct...communication with other devices (in particular, cameras and drones). Wi-Fi is a must for smartphones, but is extremely rare in traditional phones. Specifically, Wi-Fi 4 (802.11n) provides data transfer speeds of up to 600 Mbit/s and uses two frequency ranges at once - 2.4 GHz and 5 GHz, making it compatible with earlier 802.11 b/g standards and with more new Wi-Fi 5 (see below). Wi-Fi 4 is considered a relatively modest standard by modern standards, but it is still quite sufficient for most tasks.

- Wi-Fi 5 (802.11ac). The Wi-Fi standard (see above), which is the successor to Wi-Fi 4. In theory, it supports speeds of up to 6.77 Gbps, and also uses the 5 GHz band - it is less loaded with extraneous signals and more noise-resistant than the traditional 2.4 GHz. For compatibility purposes, a smartphone with a Wi-Fi 5 module may provide support for earlier standards, but it would not hurt to clarify this point separately.

- WiGig (802.11ad). Further, after Wi-Fi 5, the development of Wi-Fi standards, characterized primarily by the use of the 60 GHz band. In terms of maximum speed, it is virtually no different from Wi-Fi 5, however, the higher frequency increases the channel capacity, so that when several gadgets simultaneously communicate with one common device (for example, a router), the communication speed does not drop as much as in earlier standards. On the other hand, the 802.11ad signal is almost incapable of passing through walls; Manufacturers use various tricks to compensate for this shortcoming, but the best communication quality is still achieved only with direct visibility. Relatively little equipment for the WiGig standard is currently being produced, and it is not compatible with earlier versions of Wi-Fi; Therefore, smartphones usually provide support for other standards.

- Wi-Fi 6 (802.11ax). A standard developed as a direct development and improvement of Wi-Fi 5. Uses the ranges from 1 to 7 GHz - that is, it is capable of operating at standard frequencies of 2.4 GHz and 5 GHz (including equipment of earlier standards), and in others frequency bands. The maximum data transfer rate has increased to 10 Gbps, but the main advantage of Wi-Fi 6 was not even this, but the further optimization of the simultaneous operation of several devices on the same channel (improving the technical solutions used in Wi-Fi 5 and WiGig). Thanks to this, Wi-Fi 6 gives the lowest speed drop among modern standards when the channel is busy.

- Wi-Fi 6E (802.11ax). The Wi-Fi 6E standard is technically called 802.11ax. But unlike basic Wi-Fi 6 (for more details, see the corresponding paragraph), which is named similarly, it provides for operation in the unused 6 GHz band. In total, the standard uses 14 different frequency bands, offering high throughput in the most crowded places with many active connections. And it is backwards compatible with previous versions.

— Wi-Fi 7 (802.11be). The technology, like the previous Wi-Fi 6E, is capable of operating in three frequency ranges: 2.4 GHz, 5 GHz and 6 GHz. At the same time, the maximum bandwidth in Wi-Fi 7 was increased from 160 MHz to 320 MHz - the wider the channel, the more data it can transmit. The IEEE 802.11be standard uses 4096-QAM modulation, which also allows more symbols to be accommodated in a data transmission unit. From Wi-Fi 7 you can squeeze out a maximum theoretical information exchange speed of up to 46 Gbps. In the context of using wireless connections for streaming and video games, the implemented MLO (Multi-Link Operation) development seems very interesting. With its help, you can aggregate several channels in different ranges, which significantly reduces delays in data transmission and ensures low and stable ping. And Multi-RU (Multiple Resource Unit) technology is designed to minimize communication delays when there are many connected client devices.

— Bluetooth. Direct wireless communication technology between various devices. In mobile phones it is used primarily for connecting headphones, headsets and wrist gadgets such as fitness bracelets, but other methods of application are also possible - remote control mode, direct file transfer, etc. In modern mobile phones there can be different versions of Bluetooth, here are their features:

• Bluetooth v 4.0. A fundamental update (after version 3.0), introducing another data transmission format - Bluetooth Low Energy (LE). This protocol is designed primarily for miniature devices that transmit small amounts of information, such as fitness bracelets and medical sensors. Bluetooth LE allows you to significantly save energy during such communication.
• Bluetooth v4.1. Development and improvement of Bluetooth 4.0. One of the key improvements was the optimization of collaboration with 4G LTE communication modules - so that Bluetooth and LTE do not interfere with each other. In addition, this version makes it possible to simultaneously use a Bluetooth device in several roles - for example, to remotely control an external device while simultaneously streaming music to headphones.
• Bluetooth v4.2. Further, after 4.1, the development of the Bluetooth standard. It did not provide any fundamental updates, but received a number of improvements regarding reliability and noise immunity, as well as improved compatibility with the Internet of Things.
• Bluetooth v 5.0. Version introduced in 2016. The key innovations were the further expansion of capabilities associated with the Internet of Things. In particular, in the Bluetooth Low Energy protocol (see above), it became possible to double the data transfer rate (up to 2 Mbit/s) at the cost of reducing the range, and also quadruple the range at the cost of reducing the speed; In addition, a number of improvements have been introduced regarding simultaneous work with a large number of connected devices.
• Bluetooth v5.1. Update of the version described above v 5.0. In addition to general improvements in the quality and reliability of communication, this update introduced such an interesting feature as determining the direction from which the Bluetooth signal is coming. Thanks to this, it becomes possible to determine the location of connected devices with centimeter accuracy, which can be useful, for example, when searching for wireless headphones.
• Bluetooth v 5.2. The next update after 5.1 is Bluetooth 5 generation. The main innovations in this version are a number of security improvements, additional optimization of power consumption in LE mode and a new audio signal format for synchronizing parallel playback on multiple devices.
• Bluetooth v 5.3. The Bluetooth v 5.3 wireless protocol was introduced at the dawn of 2022. Among the innovations in it, they accelerated the process of negotiating a communication channel between the controller and the device, implemented the function of quickly switching between the operating state in a low duty cycle and a high-speed mode, and improved the throughput and stability of the communication by reducing susceptibility to interference. When unexpected interference occurs in Low Energy mode, the procedure for selecting a communication channel to switch from now on has been accelerated. There are no fundamental innovations in protocol 5.3, but a number of qualitative improvements are evident in it.
• Bluetooth v5.4. Protocol version 5.4, which was introduced at the beginning of 2023, increased the range and speed of data exchange, which is well suited for use in applications that require communication over long distances (for example, smart home systems). Also in Bluetooth v 5.4, the energy-saving BLE mode has been improved. This version of the protocol uses new security features to protect data from unauthorized access, has increased communication reliability by selecting the best channel for communication, and prevents communication losses due to interference.

- aptX support. aptX technology was developed to improve the quality of sound transmitted over Bluetooth. When transmitting sound in a regular format, without aptX, the signal is compressed quite heavily, which affects the sound quality; This is not critical when talking on the phone, but it can significantly spoil the impression of listening to music. In turn, aptX allows you to transmit an audio signal with virtually no compression and achieve sound quality comparable to a wired communication. Such features will be especially appreciated by music lovers who prefer Bluetooth headphones or wireless speakers. Of course, to use aptX, both your smartphone and external audio device must support it.

- aptX HD support. aptX HD is a further development and improvement of the original aptX technology, allowing you to transmit sound in even higher quality - Hi-Res (24-bits/48kHz). According to the creators, this standard allows you to achieve signal quality superior to AudioCD and sound purity comparable to wired communication. The latter is often questionable, but it can be argued that overall aptX HD provides very high sound quality. On the other hand, all the advantages of this technology become noticeable only on Hi-Res audio - with quality 24-bits/48kHz or higher; otherwise, the quality is limited not so much by the characteristics of the communication as by the properties of the source files.

- Support for aptX LL. A modification of aptX technology, designed to minimize signal transmission delays. Encoding and decoding a signal when transmitting audio via Blueooth with aptX inevitably takes some time; This is not critical when listening to music, but in videos or games there may be a noticeable desynchronization between the image and sound. The aptX LL technology does not have this shortcoming; it also gives a delay, but this delay is so small that a person does not notice it.

- Support for aptX Adaptive. Further development of aptX; actually combines the capabilities of aptX HD and aptX Low Latency, but is not limited to this. One of the main features of this standard is the so-called adaptive bitrate: the codec automatically adjusts the actual data transfer rate based on the characteristics of the broadcast content (music, game audio, voice communications, etc.) and the congestion of the frequencies used. This, in particular, helps reduce energy consumption and increase communication reliability; and special algorithms allow you to broadcast sound quality comparable to aptX HD (24 bits/48 kHz), using much less transmitted data. And the minimum data transfer latency (at the aptX LL level) makes this codec excellent for games and movies.

– Support for aptX Lossless. The next branch of development of aptX technology, which allows you to transmit CD-quality sound over a wireless Bluetooth network without loss or use of compression. At the same time, audio broadcasting with sampling parameters of 16 bits / 44.1 kHz is carried out with a bitrate of about 1.4 Mbit/s - this is about three times faster than in the aptX Adaptive edition. Support for aptX Lossless began to be introduced in late 2021 as part of Qualcomm's Snapdragon Sound initiative, which is available on smartphones, headphones and speakers with a Snapdragon 8 Gen 1 processor and later.

— NFC chip. NFC is a technology for wireless communication over ultra-low distances, up to 10 cm. One of the most popular applications of this technology in smartphones is contactless payments, when the device actually plays the role of a credit card: just bring the device to a terminal that supports contactless technology like PayPass or PayWave. Another common way to use NFC is to automatically connect to another NFC-compatible device via Wi-Fi or Bluetooth: gadgets brought close to each other automatically set up a communication, and the customer only needs to confirm it. Other options are technically possible: recognizing smart cards and RFID tags, using the device as a travel card, access card, etc. However, such use formats are much less common.

- Infrared port. The infrared port looks like a small “eye”, usually on the top end of the phone. This equipment allows you to turn your phone into a remote control for controlling various equipment - just install the appropriate application. At the same time, we note that among such applications you can find an option for almost any device - from TVs to air conditioners, hoods, etc. Accordingly, the “smartphone remote control” turns out to be very universal.

— Walkie-talkie. Built-in radio module that allows you to use the phone as a walkie-talkie - for communication over relatively low distances without using SIM cards. Of course, for such communication you will need another walkie-talkie (or a phone with this function). The specific frequencies supported by the built-in radio module should be clarified separately; however, all phones with this feature operate in one or more standard bands. In practice, this means that they are capable of communicating not only with similar phones, but also with classic civilian walkie-talkies - provided they match the supported bands. The communication range is usually quite low; however, the built-in walkie-talkie can be very useful for tech in situations where conventional mobile communications are ineffective or unavailable. Typical examples of such situations are staying “far from civilization”, in an area of poor treatment, or traveling abroad, where roaming is expensive.

– Satellite communication. The satellite communication function is intended to send emergency alerts to rescue services in emergency situations. Smartphones with the ability to connect to satellite frequencies can communicate with emergency services in areas where there is no mobile network treatment. For better signal reception from satellites, it is advisable for the customer to be in an open space. At the stage of function formation, only ready-made requests can be transferred. In the future, it is planned to support full messaging via satellite communications, but a separate fee will be charged for them.

The materials of which the bezel (side edging) and the back cover of the device are made.

In our catalog, this data are indicated in two words — frame material and cover material. For example, a device with a glass back and metal edging would be labeled as "metal/glass" (bezel first, then lid). Two words are specified even if the same material is used for both elements — for example, "metal/metal" for an all-metal case.

The main bezel materials include plastic, metal, glass, rubber, and ceramics. Back covers are also made mainly of plastic, metal, ceramics or rubber, and among glass there is a special variety — Gorilla glass parts. Occasionally, more specific materials are used, such as leather. Here is a more detailed description of each of these options:

— Plastic. A fairly simple, inexpensive and at the same time versatile and practical material. Actually, nowadays there are many varieties of plastic on the market, which differ in price and practical properties; so that the general property of this material depends primarily on the price category of the device. The easiest...way to give cover an unusual design is using plastic, although this design is also found in other materials. In general, all types of plastic in modern phones can be divided into glossy, matte, fluted and soft-touch. The gloss looks the shiniest, but dirt is very noticeable on it (first of all, fingerprints), moreover, such cases tend to slip in the hands. Matte surfaces are not as good-looking, but they are less sensitive to dirt. Soft touch is a special kind of matte plastic: due to the specific surface texture, this material is perceived as soft to the touch, similar to rubber. Also, it is perfectly held in the hands and almost does not slip. Fluted plastic is considered the most reliable in this regard — with signature notches on the surface; however, not everyone likes the look and feel of such surfaces when held.
As for combinations with other materials, plastic frames can be provided in metal and glass cases — for a secure hold; and plastic covers can be supplemented with metal or rubber frames for increased reliability.

— Metal. Usually metal most often means aluminium alloy. This material combines high strength, low weight and good thermal conductivity (the latter is especially important for removing heat from the hardware of performant smartphones). Metal cases are relatively rarely made in bright colours, but such a design is also possible; in addition, even without additional coloring, this material looks good. In general, it costs more than plastic, but nowadays even low cost phone models can be made of metal. At the same time, the metal frame can be combined with almost any cover material, however, such frames are especially popular in models with a glass back panel — the metal gives the case additional strength. Metal covers are found mainly among all-metal cases, less often in combination with a plastic frame (it allows you to reduce the cost and improve the permeability of the case for communication signals).

— Glass. Phone cases usually use special tempered glass of increased strength (a special kind of such glass — Gorilla Glass — is indicated separately, see below). Theoretically, glass is more sensitive to shock than most other materials, but in fact it is still quite difficult to break such a surface. At the same time, these cases look quite stylish and unusual. Their disadvantages include a rather high cost, as well as the signature features of glossy surfaces — the tendency to slip out of hands and "collect" dirt, especially fingerprints. In terms of specific body parts, glass is most often used for back covers; they are often complemented by frames made of more durable material (usually metal). But glass frames are usually part of all-glass cases — other design options do not make sense for a number of reasons.

— Gorilla Glass. A special type of high-strength glass from which back covers can be made. For glass in general, see above; and Gorilla Glass features are detailed in the Main Display section. We only note that, as in displays, different versions of such glass can be used in the rear panels of the case, differing in resistance to shock and scratches.

— Rubber. Usually, in this case we are talking about a body or a frame made of a hard material (plastic or metal) with an additional rubber coating. The use of such a coating is an unmistakable sign of a phone with a high degree of protection — waterproof, and often also shockproof. Rubber is the optimal material for such devices: it perfectly resists both moisture and shock, well insulates the hardware from cold and heat, while such a surface is pleasant to the touch and does not slip in the hand. The main drawback of this material is its bulkiness: the rubber coating must be quite thick, so that it noticeably affects the dimensions of the device. Thus, it makes sense to pay attention to this option in occasions where security is more important for you than compactness. At the same time, we note that the rubber case can be combined with a metal frame, and the rubber frame can be installed on a plastic device; these options also turn out to be quite reliable.

— Ceramics. Ceramics is material made by sintering raw materials at high temperatures. Mobile phones use special high-strength types of such materials. The advantages of ceramics include a stylish appearance and good reliability in most situations. On the other hand, such compositions are still quite sensitive to impacts (especially point impacts), they tend to slip in the hands, and they are not cheap. Therefore, ceramics is rarely used in modern mobile phones — mainly as a fashion material in fairly advanced models. Most of these models combine a ceramic lid with a metal frame; all-ceramic cases are noticeably less common.

— Leather. A rather rare and specific material, used mainly as a design solution. Leather covering in such cases is provided for the back cover, while the frame is made of metal or plastic. This material gives the device a solid appearance, emphasizing the status of the owner; in addition, it is pleasant to the touch and does not allow the device to slip out of the hand. However, leather is expensive and not reliable: it is easily scratched and torn even with light contact with sharp objects, and is also prone to abrasion. Therefore, such cases are not popular even among high-end phones.