Samsung Galaxy S4

The Samsung Galaxy S4 is an Android smartphone produced by Samsung Electronics and was first shown publicly on March 14, 2013 at Samsung Mobile Unpacked in New York City. It is the successor to the Galaxy S III which maintains a similar design, but with upgraded hardware and an increased focus on software features that take advantage of its hardware capabilities—such as the ability to detect when a finger is hovered over the screen, and expanded eye tracking functionality.^[8][9] A hardware variant of the S4 became the first smartphone to support the emerging LTE Advanced mobile network standard.^[11]

The S4 was made available in late April 2013 on 327 carriers in 155 countries.^[12] It became Samsung's fastest selling smartphone, with 20 million sold worldwide in the first two months,^[13] and 40 million in the first six months

Hardware[edit]

The Samsung Galaxy S4 uses a refined version of the hardware design introduced by the Samsung Galaxy S III, with a rounded, polycarbonate chassis and a removable rear cover. It is slightly lighter and narrower than the Samsung Galaxy S III, with a length of 136.6 mm (5.38 in), a width of 69.8 mm (2.75 in), and a thickness of 7.9 mm (0.31 in). At the bottom of the device is a microphone and a microUSB port for data connections and charging; it also supportsUSB-OTG and MHL 2.0. Near the top of the device are a front-facing camera, infrared, proximity, and ambient light sensors, and a notification LED. In particular, the infrared sensor is used for the device's "Air View" features. Aheadphone jack, secondary microphone and infrared blaster are located at the top.^[15] The S4 is widely available in black and white color finishes; in selected regions, Samsung also introduced versions in red, purple, pink, brown with gold trim, and light pink with gold trim.^{[16][17][18][19]} In late-January 2014, Samsung's Russian website briefly listed a new black model with a plastic leather backing, similar to the Galaxy Note 3.^[20] The S4's display is larger than its predecessor, with a 5-inch (130 mm), 1080p PenTile RGBG Super AMOLED screen with a resolution of 441 PPI, andCorning Gorilla Glass 3.^[15] Unlike previous models, the S4 does not contain FM radio support, citing the increased use of online media outlets for content consumption on mobile devices.^[21]

Galaxy S4 models use one of two processors, depending on the region and network compatibility. The S4 version for North America, most of Europe, parts of Asia, and other countries contains Qualcomm's Snapdragon 600 system-on-chip, containing a quad-core 1.9 GHz Krait 300 CPU and an Adreno 320 GPU. The chip also contains a modem which supports LTE.^[22][23] Other models include Samsung's Exynos 5 Octa system-on-chip with a heterogeneous CPU. Theocta-core CPU comprises a 1.6 GHz quad-core Cortex-A15 cluster and a 1.2 GHz quad-core Cortex-A7 cluster.^[12][24]The chip can dynamically switch between the two clusters of cores based on CPU usage; the chip switches to the A15 cores when more processing power is needed, and stays on the A7 cores to conserve energy on lighter loads. Only one of the clusters is used at any particular moment, and software sees the processor as a single quad-core CPU.^[22][24][25] The SoC also contains an IT tri-core PowerVR SGX 544 graphics processing unit (GPU). Regional models of the S4 vary in support for LTE; for Exynos 5-based models, while the E300K/L/S versions support LTE, with the Cortex-A15 also clocked at 1.6 GHz.^[26][27][28] the GT-I9500 model does not.^[29] The S4 GT-I9505 includes a multiband LTE transceiver.^[8]

On 24 June 2013, a variant supporting LTE Advanced, the first commercially available device to do so, was announced for South Korea.^[11]

The S4 comes with either 16 GB, 32 GB or 64 GB of internal storage, which can be supplemented with up to an additional 64 GB with a microSD card slot.^[30] The S4 contains a 2600 mAh, NFC-enabled battery

The S4 was originally released with Android 4.2.2 and Samsung's TouchWiz Nature UX 2interface. Head tracking features have been extended on the S4; the new "Smart Scroll" feature can be used to scroll while looking at the screen by slightly tilting head or phone forward or backward,^[31] and "Smart Pause" allows the video player to pause videos if the user is not looking at the screen. "Air View" and "Air Gestures" implement gestures and other functionality (such as previewing images or messages) by holding or swiping a hand or finger slightly above the screen, similarly to Samsung's Galaxy Note series, and adds a feature known as "Quick Glance", which uses the proximity sensor to wake the phone so it can display notifications. The "Group Play" feature allows ad hoc sharing of files between Galaxy phones, along with multiplayer games and music streaming between S4 phones. The S4 also introduces Knox in the Android 4.3 update, a suite of features which implements a sandbox for enterprise environments that can co-exist with a user's "personal" data. Knox incorporates use of the ARM TrustZone extensions and security enhancements to the Android platform.^[32]

The camera app implements numerous new features (some of which were first seen on the Galaxy Camera), including an updated interface, and new modes such as "Drama" (which composes a moving element from multiple shots into a single photo), "Eraser" (which takes multiple shots and allows the user to remove unnecessary elements from a picture), "Dual Shot" (which uses the front-facing camera for a picture-in-picture effect), "Sound and Shot" (which allows the user to record a voice clip alongside a photo), "Animated Photo", and "Story Album" among others. The S4 also supports High Efficiency Video Coding (HEVC), a next-generation video codec.^[8][9][33] Other new pre-loaded apps include WatchOn (anelectronic program guide that can utilize the S4's infrared transmitter to be a remote control), S Translator, the workout tracker S Health, S Voice Drive, S Memo, TripAdvisor, and an optical character recognition app.^[34] The previous "Hub" apps from past Samsung devices were replaced by a single Samsung Hub app, with access to music, e-books, and games that can be purchased by users.^[15] To take a screenshot a user can can simply swipe their hand on the screen from one end to other horizontally