Google Rollout Android 5.1 Lollipop
Google Just announced the availability of the Android 5.1 (Hammerhead) on their official repository. The Update said improves the stability and performance and offers new features like supportfor multi-SIM cards, Device protection and High Definition (HD) voice on some compatible devices.
Added security is the Device is protected when your phone is stolen or lost it will remain locked until you sign in with your Google Account even if someone resets your device to factory settings. this feature will be available in the upcoming devices that shipped with Android 5.1.
It also provides a quick access of controls with Wi-Fi and Bluetooth paired devices.
In case you want to have the official image file it’s already available at the Google Android Repository.