On this update Google is going to fix all the bug and issues that have been raised With Android 5.0 Lollipop. Other that this Android 5.1 will receive a improve in features like ‘Device Protection’ integration which helps manage or track lost or stolen devices remotely.
Google says mentioned that your lost or stolen device will remain locked until you sign in with your Google account, even if someone resets your device to factory settings. Additionally, Android 5.1 will facilitate users to have high-definition voice calling
Apart from this Android 5.1 will also receive some of the minor improvements such as faster ways to join Wi-Fi or pair with Bluetooth devices. Lollipop is also now compatible with devices that have multiple SIM slots.