Android is a mobile operating system based on a modified version of the Linux kernel and other open-source software, designed primarily for touchscreen mobile devices such as smartphones and tablets. Android has historically been developed by a consortium of developers known as the Open Handset Alliance, but its most widely used version is primarily developed by Google. It was unveiled in November 2007, with the first commercial Android device, the HTC Dream, being launched in September 2008.
At its core, the operating system is known as the Android Open Source Project (AOSP) and is free and open-source software (FOSS) primarily licensed under the Apache License. However, most devices run on the proprietary Android version developed by Google, which ships with additional proprietary closed-source software pre-installed,[6] most notably Google Mobile Services (GMS)[7] which includes core apps such as Google Chrome, the digital distribution platform Google Play, and the associated Google Play Services development platform. Firebase Cloud Messaging is used for push notifications. While AOSP is free, the “Android” name and logo are trademarks of Google, which imposes standards to restrict the use of Android branding by “uncertified” devices outside their ecosystem.
Over 70 percent of smartphones based on the Android Open Source Project run Google’s ecosystem (which is known simply as Android), some with vendor-customized user interfaces and software suites, such as TouchWiz and later One UI by Samsung and HTC Sense. Competing ecosystems and forks of AOSP include Fire OS (developed by Amazon), ColorOS by Oppo, OriginOS by Vivo, MagicUI by Honor, and custom ROMs such as LineageOS; and Meta Horizon OS for VR headsets.
The source code has been used to develop variants of Android on a range of other electronics, such as game consoles, digital cameras, portable media players, and PCs, each with a specialized user interface. Some well-known derivatives include Android TV for televisions and Wear OS for wearables, both developed by Google. Software packages on Android, which use the APK format, are generally distributed through proprietary application stores like Google Play Store, Amazon Appstore, Samsung Galaxy Store, Huawei AppGallery, Cafe Bazaar, GetJar, and Aptoide, or open source platforms like F-Droid.
Android has been the best-selling OS worldwide on smartphones since 2011 and on tablets since 2013. As of May 2021, it had over three billion monthly active users, the largest installed base of any operating system in the world,[11] and as of 2024, the Google Play Store features 1.7 million apps, a decline from its of peak of over 3 million apps.[12] Android 14, released on October 4, 2023, is the latest version, and Android 12.1/12L includes improvements specific to foldable phones, tablets, desktop-sized screens[13] and Chromebooks.
What are Android OS features?
The default UI of Android relies on direct manipulation inputs such as tapping, swiping and pinching to initiate actions. The device provides haptic feedback to the user via alerts such as vibrations to respond to actions. If a user presses a navigation button, for example, the device vibrates.
When a user boots a device, Android OS displays the home screen, which is the primary navigation hub for Android devices and is comprised of widgets and app icons. Widgets are informational displays that automatically update content such as weather or news. The home screen display can differ based on the device manufacturer that is running the OS. Users can also choose different themes for the home screen via third-party apps on Google Play.
A status bar at the top of the home screen displays information about the device and its connectivity, such as the Wi-Fi network that the device is connected to or signal strength. Users can pull down the status bar with a swipe of a finger to view a notification screen.
Android OS also includes features to save battery usage. The OS suspends applications that aren’t in use to conserve battery power and CPU usage. Android includes memory management features that automatically close inactive processes stored in its memory.
Additionally, Android OS has generative AI features that improve Google searches. The Circle to Search feature allows users to highlight, circle, scribble or tap on images, videos or text in search to learn more about elements of the photo. Users can also point the smartphone camera and ask questions about what the camera sees using the Google app. The feature is available on high-end Android phones, including the Pixel 8 and Pixel 8 Pro.
Android runs on both of the most widely deployed cellular standards, GSM/HSDPA and CDMA/EV-DO. Android also supports:
- Bluetooth
- Edge
- 3G communication protocols, like EV-DO and HSDPA
- Wi-Fi
- Autocorrect
- SMS and MMS messaging
- video/still digital cameras
- GPS
- compasses
- accelerometers
- accelerated 3D graphics
- multitasking applications
Android OS versions
Google makes incremental changes to the OS with each release. This often includes security patches and performance improvements.
- Android 1.0. Released Sept. 23, 2008. Included a suite of Google apps, including Gmail, Maps, Calendar and YouTube.
- Android 1.5 (Cupcake). Released April 27, 2009. Introduced an onscreen virtual keyboard and the framework for third-party app widgets.
- Android 1.6 (Donut). Released Sept. 15, 2009. Introduced the ability for the OS to run on different screen sizes and resolutions; added support for CDMA networks.
- Android 2.0 (Eclair). Released Oct. 26, 2009. Added turn-by-turn voice navigation, real-time traffic information, pinch-to-zoom capability.
- Android 2.2 (Froyo). Released May 20, 2010. Added dock at the bottom of the home screen and voice actions, which allows users to tap an icon and speak a command. Also introduced support for Flash to the web browser.
- Android 2.3 (Gingerbread). Released Dec. 6, 2010. Introduced black and green into the UI.
- Android 3.0 to 3.2 (Honeycomb). Released Feb. 22, 2011. This release was exclusive to tablets and introduced a blue, space-themed holographic design.
- Android 4.0 (Ice Cream Sandwich). Released Oct. 18, 2011. Introduced a unified UI to both tablets and smartphones; emphasized swiping as a navigational method.
- Android 4.1 to 4.3 (Jelly Bean). Released July 9, 2012, Nov. 13, 2012, and July 24, 2013, respectively. Introduced Google Now, a day planner service. Added interactive notifications and improved voice search system.
- Android 4.4 (KitKat). Released Oct. 31, 2013. Introduced lighter colors into the UI, along with a transparent status bar and white icons.
- Android 5.0 (Lollipop). Released Nov. 12, 2014. Incorporated a card-based appearance in the design with elements such as notifications and Recent Apps list. Introduced hands-free voice control with the spoken “OK, Google” command.
- Android 6.0 (Marshmallow). Released Oct. 5, 2015. This release marked Google’s adoption of an annual release schedule. Introduced more granular app permissions and support for USB-C and fingerprint readers.
- Android 7.0 and 7.1 (Nougat). Released Aug. 22, 2016 and Oct. 4, 2016, respectively. Introduced a native split-screen mode and the ability to bundle notifications by app.
- Android 8.0 and 8.1 (Oreo). Released Aug. 21, 2017 and Dec. 5, 2017, respectively. These versions introduced a native picture-in-picture (PIP) mode and the ability to snooze notifications. Oreo was the first version to incorporate Project Treble, an effort by OEMs to provide more standardized software updates.
- Android 9.0 (Pie). Released Aug. 6, 2018. This version replaced Back, Home and Overview buttons for a multifunctional Home button and a smaller Back button. Introduced productivity features, including suggested replies for messages and brightness management capabilities.
- Android 10 (Android Q). Released Sept. 3, 2019. Abandoned the Back button in favor of a swipe-based approach to navigation. Introduced a dark theme and Focus Mode, which enables users to limit distractions from certain apps.
- Android 11 (Red Velvet Cake). Released Sept. 8, 2020. Added built-in screen recording. Created a single location to view and respond to conversations across multiple messaging apps. This version also updated the chat bubbles so users can pin conversations to the top of apps and screens.
- Android 12 (Snow Cone). Released Oct. 4, 2021. Added customization options for the user interface. The conversation widget let users store preferred contacts on their home screens. Added more privacy options, including sharing when apps access information such as camera, photos or microphone.
- Android 12L. Released March 7, 2022.The L stands for larger screens. This update aimed to improve the user interface and optimize for the larger screen of a tablet, foldable or Chromebook. This update added a dual-panel notification center for tablets and foldables.
- Android 13 (Tiramisu). Released Aug. 15, 2022. Included more customizable options including color, theme, language and music. Security updates included control over information apps can access, notification permission required for all apps and clearing of personal information on clipboard. This update enables multitasking by sharing of messages, chats, links and photos across multiple Android devices — including phones, tablets and Chromebooks.
- Android 14 (Upside Down Cake). Released Oct. 4, 2023. Included more customization options for the lock screen and wallpapers. OS efficiency was improved to decrease the strain on a phone’s battery. For accessibility, Google added larger scalable fonts for vision-impaired users and camera flashes to give hearing-impaired users another visual cue when they get a notification. Security updates include notifications of changes in data-sharing policies for third-party applications, enhanced PIN security features and better support for passkey authentication across more applications.