A typical smartphone contains a number of
metal–oxide–semiconductor (MOS)
integrated circuit (IC) chips, which in turn contain billions of tiny
MOS field-effect transistors (MOSFETs). A typical smartphone contains the following MOS IC chips: •
RF power amplifier (
LDMOS) Some are also equipped with an
FM radio receiver, a hardware
notification LED, and an infrared transmitter for use as
remote control. A few models have additional
sensors such as
thermometer for measuring ambient temperature,
hygrometer for humidity, and a sensor for
ultraviolet ray measurement. A few smartphones designed around specific purposes are equipped with uncommon hardware such as a projector (
Samsung Beam i8520 and
Samsung Galaxy Beam i8530),
optical zoom lenses (
Samsung Galaxy S4 Zoom and
Samsung Galaxy K Zoom),
thermal camera, and even
PMR446 (
walkie-talkie radio)
transceiver.
Central processing unit Smartphones have
central processing units (CPUs), similar to those in computers, but optimised to operate in low power environments. In smartphones, the CPU is typically integrated in a
CMOS (complementary
metal–oxide–semiconductor)
system-on-a-chip (SoC)
application processor. but also on the
memory hierarchy. Because of these challenges, the performance of mobile phone CPUs is often more appropriately given by scores derived from various standardized tests to measure the real effective performance in commonly used applications.
Buttons user interface as of 2013, accessed by holding the power button for a second , a 2010 smartphone with
optical trackpad and search button Smartphones are typically equipped with a power button and volume buttons. Some pairs of volume buttons are unified. Some are equipped with a dedicated camera shutter button. Units for outdoor use may be equipped with an "SOS" emergency call and "PTT" (
push-to-talk button). The presence of physical front-side buttons such as the
home and navigation buttons has decreased throughout the 2010s, increasingly becoming replaced by capacitive touch sensors and simulated (on-screen) buttons. As with classic mobile phones, early smartphones such as the
Samsung Omnia II were equipped with buttons for accepting and declining phone calls. Due to the advancements of functionality besides phone calls, these have increasingly been replaced by navigation buttons such as "menu" (also known as "options"), "back", and "tasks". Some early 2010s smartphones such as the
HTC Desire were additionally equipped with a "Search" button (🔍) for quick access to a web search engine or apps' internal search feature. Since 2013, smartphones' home buttons started integrating
fingerprint scanners, starting with the
iPhone 5s and
Samsung Galaxy S5. Functions may be assigned to button combinations. For example,
screenshots can usually be taken using the home and power buttons, with a short press on iOS and one-second holding Android OS, the two most popular mobile operating systems. On smartphones with no physical home button, usually the volume-down button is instead pressed with the power button. Some smartphones have a screenshot and possibly
screencast shortcuts in the navigation button bar or the power button menu.
Display One of the main characteristics of smartphones is the
screen. Depending on the device's design, the screen fills most or nearly all of the space on a device's front surface. Many smartphone displays have an
aspect ratio of
16:9, but taller aspect ratios became more common in 2017, as well as the aim to eliminate bezels by extending the display surface to as close to the edges as possible.
Screen sizes Screen sizes are measured in diagonal
inches. Phones with screens larger than 5.2 inches are often called "
phablets". Smartphones with screens over 4.5 inches in size are commonly difficult to use with only a single hand, since most thumbs cannot reach the entire screen surface; they may need to be shifted around in the hand, held in one hand and manipulated by the other, or used in place with both hands. Due to design advances, some modern smartphones with large screen sizes and "edge-to-edge" designs have compact builds that improve their ergonomics, while the shift to taller aspect ratios have resulted in phones that have larger screen sizes whilst maintaining the ergonomics associated with smaller 16:9 displays.
Panel types Liquid-crystal displays (LCDs) and
organic light-emitting diode (OLED) displays are the most common. Some displays are integrated with pressure-sensitive digitizers, such as those developed by
Wacom and
Samsung, and Apple's
Force Touch system. A few phones, such as the
YotaPhone prototype, are equipped with a low-power
electronic paper rear display, as used in
e-book readers.
Alternative input methods derivative, reveals the full URL by hovering over the
tab list using the stylus on a
Samsung Galaxy Note 4. , 2010 Some devices are equipped with additional input methods such as a
stylus for higher precision input and hovering detection or a
self-capacitive touch screens layer for floating finger detection. The latter has been implemented on few phones such as the
Samsung Galaxy S4,
Note 3,
S5,
Alpha, and
Sony Xperia Sola, making the Galaxy Note 3 the only smartphone with both so far. Hovering can enable preview
tooltips such as on the
video player's seek bar, in text messages, and quick contacts on the
dial pad, as well as
lock screen animations, and the simulation of a
hovering
mouse cursor on web sites. Some styluses support hovering as well and are equipped with a button for quick access to relevant tools such as digital
post-it notes and highlighting of text and elements when dragging while pressed, resembling drag selection using a
computer mouse. Some series such as the
Samsung Galaxy Note series and
LG G Stylus series have an integrated tray to store the stylus in. Few devices such as the
iPhone 6s until
iPhone Xs and
Huawei Mate S are equipped with a
pressure-sensitive touch screen, where the pressure may be used to simulate a gas pedal in video games, access to preview windows and shortcut menus, controlling the typing cursor, and a weight scale, the latest of which has been rejected by Apple from the
App Store. Some early 2010s HTC smartphones such as the
HTC Desire (Bravo) and
HTC Legend are equipped with an optical track pad for scrolling and selection.
Notification light Many smartphones except Apple iPhones are equipped with low-power
light-emitting diodes besides the screen that are able to notify the user about incoming messages, missed calls, low battery levels, and facilitate locating the mobile phone in darkness, with marginial power consumption. To distinguish between the sources of notifications, the colour combination and blinking pattern can vary. Usually three diodes in red, green, and blue (
RGB) are able to create a multitude of colour combinations.
Sensors Smartphones are equipped with a multitude of sensors to enable system features and third-party applications.
Common sensors Accelerometers and
gyroscopes enable automatic control of screen rotation. Uses by third-party software include
bubble level simulation. An
ambient light sensor allows for automatic screen brightness and contrast adjustment, and an
RGB sensor enables the adaption of screen colour. Many mobile phones are also equipped with a
barometer sensor to measure air pressure, such as Samsung since 2012 with the
Galaxy S3, and Apple since 2014 with the
iPhone 6. It allows estimating and detecting changes in altitude. A
magnetometer can act as a
digital compass by measuring
Earth's magnetic field.
Rare sensors Samsung equips their flagship smartphones since the 2014
Galaxy S5 and
Galaxy Note 4 with a
heart rate sensor to assist in fitness-related uses and act as a shutter key for the front-facing camera. So far, only the 2013
Samsung Galaxy S4 and
Note 3 are equipped with an
ambient temperature sensor and a
humidity sensor, and only the
Note 4 with an
ultraviolet radiation sensor which could warn the user about excessive exposure. A rear infrared
laser beam for distance measurement can enable
time-of-flight camera functionality with accelerated
autofocus, as implemented on select LG mobile phones starting with
LG G3 and
LG V10. Due to their currently rare occurrence among smartphones, not much software to utilize these sensors has been developed yet.
Storage While
eMMC (
embedded multi media card)
flash storage was most commonly used in mobile phones, its successor,
UFS (
Universal Flash Storage) with higher transfer rates emerged throughout the 2010s for upper-class devices. ;Capacity While the internal storage capacity of mobile phones has been near-stagnant during the first half of the 2010s, it has increased steeper during its second half, with
Samsung for example increasing the available internal storage options of their flagship class units from 32 GB to 512 GB within only 2 years between 2016 and 2018.
Memory cards The space for data storage of some mobile phones can be expanded using
MicroSD memory cards, whose capacity has multiplied throughout the 2010s (→ ). Benefits over
USB on the go storage and
cloud storage include
offline availability and
privacy, not reserving and protruding from the
charging port, no connection instability or
latency, no dependence on voluminous
data plans, and preservation of the limited rewriting cycles of the device's permanent internal storage. Large amounts of data can be moved immediately between devices by changing memory cards, large-scale
data backups can be created offline, and data can be read externally should the smartphone be inoperable. In case of technical
defects which make the device unusable or
unbootable as a result of liquid damage, fall damage, screen damage,
bending damage,
malware, or bogus
system updates, etc., data stored on the memory card is likely
rescueable externally, while data on the inaccessible internal storage would be
lost. A memory card can usually immediately be re-used in a different memory-card-enabled device with no necessity for prior
file transfers. Some
dual-SIM mobile phones are equipped with a hybrid slot, where one of the two slots can be occupied by either a
SIM card or a memory card. Some models, typically of higher end, are equipped with three slots including one dedicated memory card slot, for simultaneous dual-SIM and memory card usage. ;Physical location The location of both SIM and memory card slots vary among devices, where they might be located accessibly behind the back cover or else behind the battery, the latter of which denies
hot swapping. Mobile phones with non-removable rear cover typically house SIM and memory cards in a small tray on the handset's frame, ejected by inserting a needle tool into a pinhole. Some earlier mid-range phones such as the 2011
Samsung Galaxy Fit and
Ace have a sideways memory card slot on the frame covered by a cap that can be opened without tool.
File transfer Originally,
mass storage access was commonly enabled to computers through USB. Over time, mass storage access was removed, leaving the
Media Transfer Protocol as protocol for USB file transfer, due to its non-exclusive access ability where the computer is able to access the storage without it being locked away from the mobile phone's software for the duration of the connection, and no necessity for common
file system support, as communication is done through an
abstraction layer. However, unlike mass storage, Media Transfer Protocol lacks parallelism, meaning that only a single transfer can run at a time, for which other transfer requests need to wait to finish. This, for example, denies browsing photos and playing back videos from the device during an active file transfer. Some programs and devices lack support for MTP. In addition, the direct access and
random access of files through MTP is not supported. Any file is wholly downloaded from the device before opened.
Sound Some audio quality enhancing features, such as
Voice over LTE and
HD Voice have appeared and are often available on newer smartphones. Sound quality can remain a problem due to the design of the phone, the quality of the cellular network and compression algorithms used in
long-distance calls. Audio quality can be improved using a
VoIP application over
Wi-Fi. Cellphones have small speakers so that the user can use a
speakerphone feature and talk to a person on the phone without holding it to their ear. The small speakers can also be used to listen to digital audio files of music or speech or watch videos with an audio component, without holding the phone close to the ear. However, integrated speakers may be small and of restricted sound quality to conserve space. Some mobile phones such as the
HTC One M8 and the
Sony Xperia Z2 are equipped with
stereophonic speakers to create spacial sound when in horizontal orientation.
Audio connector The
3.5mm headphone receptible (
coll. "
headphone jack") allows the immediate operation of passive
headphones, as well as connection to other external auxiliary audio appliances. Among devices equipped with the connector, it is more commonly located at the bottom (charging port side) than on the top of the device. The decline of the connector's availability among newly released mobile phones among all major vendors commenced in 2016 with its lack on the Apple
iPhone 7. An
adapter reserving the charging port can retrofit the plug. Battery-powered, wireless Bluetooth headphones are an alternative. Those tend to be costlier however due to their need for internal hardware such as a Bluetooth
transceiver and a battery with a charging controller, and a Bluetooth coupling is required ahead of each operation.
Battery Smartphones typically feature
lithium-ion or
lithium-polymer batteries due to their high
energy densities. Batteries chemically wear down as a result of repeated charging and discharging throughout ordinary usage, losing both energy capacity and output power, which results in loss of processing speeds followed by system outages. Battery capacity may be reduced to 80% after few hundred recharges, and the drop in performance accelerates with time. Some mobile phones are designed with batteries that can be interchanged upon expiration by the end user, usually by opening the back cover. While such a design had initially been used in most mobile phones, including those with touch screen that were not Apple iPhones, it has largely been usurped throughout the 2010s by permanently built-in, non-replaceable batteries; a design practice criticized for
planned obsolescence.
Charging (
power bank) Due to limitations of
electrical currents that existing USB cables' copper wires could handle, charging protocols which make use of elevated
voltages such as
Qualcomm Quick Charge and
MediaTek Pump Express have been developed to increase the power throughput for faster charging, to maximize the usage time without restricted ergonomy and to minimize the time a device needs to be attached to a power source. The smartphone's integrated
charge controller (IC) requests the elevated voltage from a supported
charger. "
VOOC" by Oppo, also marketed as "dash charge", took the counter approach and increased current to cut out some heat produced from internally regulating the arriving voltage in the end device down to the battery's charging terminal voltage, but is incompatible with existing USB cables, as it requires the thicker copper wires of high-current USB cables. Later,
USB Power Delivery (
USB-PD) was developed with the aim to standardize the negotiation of charging parameters across devices of up to 100 Watts, but is only supported on cables with USB-C on both endings due to the connector's dedicated PD channels. While charging rates have been increasing, with 15
watts in 2014, 20 Watts in 2016, and 45 watts in 2018, the power throughput may be throttled down significantly during operation of the device.
Wireless charging has been widely adapted, allowing for intermittent recharging without wearing down the charging port through frequent reconnection, with
Qi being the most common standard, followed by
Powermat. Due to the lower efficiency of wireless power transmission, charging rates are below that of wired charging, and more heat is produced at similar charging rates. By the end of 2017, smartphone battery life has become generally adequate; however, earlier smartphone battery life was poor due to the weak batteries that could not handle the significant power requirements of the smartphones' computer systems and color screens. Smartphone users purchase additional chargers for use outside the home, at work, and in cars and by buying portable external "battery packs". External battery packs include generic models which are connected to the smartphone with a cable, and custom-made models that "piggyback" onto a smartphone's case. In 2016, Samsung had to recall millions of the
Galaxy Note 7 smartphones due to an explosive battery issue. For consumer convenience,
wireless charging stations have been introduced in some hotels, bars, and other public spaces.
Power management A technique to minimize power consumption is the panel self-refresh, whereby the image to be shown on the display is not sent at all times from the processor to the integrated controller (IC) of the display component, but only if the information on screen is changed. The display's integrated controller instead memorizes the last screen contents and refreshes the screen by itself. This technology was introduced around 2014 and has reduced power consumption by a few hundred milliwatts.
Cameras Cameras have become standard features of smartphones. phone cameras are now a highly competitive area of differentiation between models, with advertising campaigns commonly based on a focus on the quality or capabilities of a device's main cameras. Images are usually saved in the
JPEG file format; some high-end phones since the mid-2010s also have
RAW imaging capability.
Space constraints Typically smartphones have at least one main rear-facing camera and a lower-resolution front-facing camera for "
selfies" and
video chat. Owing to the limited depth available in smartphones for
image sensors and
optics, rear-facing cameras are often housed in a "bump" that is thicker than the rest of the phone. Since increasingly thin mobile phones have more abundant horizontal space than the depth that is necessary and used in dedicated cameras for better lenses, there is additionally a trend for phone manufacturers to include multiple cameras, with each optimized for a different purpose (
telephoto,
wide angle, etc.). Viewed from back, rear cameras are commonly located at the top center or top left corner. A cornered location benefits by not requiring other hardware to be packed around the camera module while increasing
ergonomy, as the lens is less likely to be covered when held horizontally. Modern advanced smartphones have cameras with
optical image stabilisation (OIS), larger sensors, bright lenses, and even optical zoom plus
RAW images.
HDR, "
Bokeh mode" with multi lenses and multi-shot
night modes are now also familiar. Many new smartphone camera features are being enabled via
computational photography image processing and multiple specialized lenses rather than larger sensors and lenses, due to the constrained space available inside phones that are being made as slim as possible.
Dedicated camera button Some mobile phones such as the
Samsung i8000 Omnia 2, some
Nokia Lumias and some
Sony Xperias are equipped with a physical camera shutter button. Those with two pressure levels resemble the
point-and-shoot intuition of dedicated
compact cameras. The camera button may be used as a
shortcut to quickly and
ergonomically launch the camera software, as it is located more accessibly inside a pocket than the power button.
Back cover materials Back covers of smartphones are typically made of
polycarbonate, aluminium, or glass. Polycarbonate back covers may be glossy or matte, and possibly textured, like dotted on the
Galaxy S5 or leathered on the
Galaxy Note 3 and
Note 4. While polycarbonate back covers may be perceived as less "premium" among
fashion- and
trend-oriented users, its utilitarian strengths and technical benefits include durability and shock absorption, greater
elasticity against permanent bending like metal, inability to shatter like glass, which facilitates designing it removable; better manufacturing cost efficiency, and no blockage of radio signals or wireless power like metal.
Accessories A wide range of accessories are sold for smartphones, including
cases,
memory cards,
screen protectors,
chargers,
wireless power stations,
USB On-The-Go adapters (for connecting USB drives and or, in some cases, a HDMI cable to an external monitor),
MHL adapters, add-on batteries,
power banks,
headphones, combined headphone-microphones (which, for example, allow a person to privately conduct
calls on the device without holding it to the ear), and
Bluetooth-enabled
powered speakers that enable users to listen to media from their smartphones wirelessly. Cases range from relatively inexpensive rubber or soft plastic cases which provide moderate protection from bumps and good protection from scratches to more expensive, heavy-duty cases that combine a rubber padding with a hard outer shell. Some cases have a "book"-like form, with a cover that the user opens to use the device; when the cover is closed, it protects the screen. Some "book"-like cases have additional pockets for credit cards, thus enabling people to use them as
wallets. Accessories include products sold by the manufacturer of the smartphone and compatible products made by other manufacturers. However, some companies, like
Apple, stopped including chargers with smartphones in order to "reduce
carbon footprint", etc., causing many customers to pay extra for charging adapters. ==Software==