Google has officially announced the launch of the mobile operating system update Android to version Android 5.1 Lollipop, which improves the performance and stability of the system as a whole, and also offers a number of new features, including 'native' support for working with multiple SIM cards, device protection function (Device Protection) and support for HD voice codecs on compatible devices.
As noted above, this update brings initial support to the operating system kernel Android for the ability to work with multiple SIM cards, whereas previously this limitation was circumvented by installing third-party applications (most often from the manufacturer).
The 'Device Protection' feature allows the device to remain locked even after a factory reset in the event of a loss or theft, until the user logs in with their account.
Support for the HD Voice codec will improve the quality of speech transmission when talking on compatible devices and support from the operator. Initially it will be a Nexus 6 'phablet' and T-Mobile or Verizon in the North American market.
In addition, Android 5.1 Lollipop also provides advanced functionality, such as the ability to connect to a Wi-Fi network and manage your paired devices Bluetooth directly from the quick settings panel.