Android, an open-source operating system developed by Google, was launched on October 22, 2008, with the T-Mobile G1 and has undergone numerous updates since. Key features like multi-touch capability, an on-screen keyboard, and a robust notification system have evolved through various versions, culminating in significant releases like Ice Cream Sandwich and KitKat. The OS has dramatically transformed from simple functionalities to a comprehensive smartphone platform, integrating features such as Google Now and enhanced multitasking.