This document discusses the evolution of Android versions from 1.6 Donut to 7.0 Nougat. It provides details on the key features introduced in each major version: - Versions 1.6 to 2.2 focused on improvements like Bluetooth support, digital zoom, live wallpapers, and apps to SD card support. - Versions 2.3 to 4.3 added features like NFC support, Face Unlock, improved notifications, and support for Google Now. - Versions 4.4 to 5.1 brought material design, battery optimizations, encryption if devices are lost or stolen, and quick settings. - Versions 6.0 to 6.1 included USB