History

• Android is the world’s most popular smartphone operating system, and is common on phones by Samsung, Xiao Mi, LG, Sony, Lenovo and many other phone vendors.
• Android is based on Linux, the free, open source operating system kernel created by Linux Torvalds.
• Android was purchased by Google at an early stage in its development, and turned into an open source project.
• Whilst lots of Android is open source (and can be downloaded from the AOSP Project), many essential tools such as the Play Store are commercial, and controlled by Google.
• Google licenses Android to phone manufacturers, who try to distinguish themselves by adding their own front-end software on top of the Android core and Google’s tools. Often this software is superfluous and slows down the whole phone:
  • One example of such software is Samsung’s TouchWiz:

• If you want to use “stock Android” (Google’s Android, without extra software), you can purchase a Nexus device, or flash a custom ROM onto your phone.