The rumors that Google would soon launch a major update to Android 5.0 Lollipop have turned out to be true – the US tech giant has officially launched Android 5.1, which happens to bring a few more features to the already released Android 5.0 Lollipop.
Android 5.1 is designed to improve both performance and stability and includes a few new features such as support for multiple SIM cards, support for HD voice calls on compatible devices and networks, and the ability to join Wi-Fi networks and pair Bluetooth devices right from the Quick Settings menu. While this is all good, Android 5.1 Lollipop brings a major new feature as well – called Device Protection the new feature locks a device until its owner signs in with their Google account. Moreover the lock remains even if the device gets factory reset, which pretty much makes stealing an Android 5.1 smartphone with Device Protection meaningless.
The new Android 5.1 will soon be available to Nexus and Google Play edition devices and later to various new smartphones.
Source: Anandtech.com