Avira – Free Antivirus
Avira, also known on PC for its formidable efficiency, speed and low resource consumption, is pleasantly found on Android. Not that the mobile version of the antivirus is a beast in search of viruses, but it adopts an interface as simplified as possible and which goes to the point, as long as you have created an account.
For the rest, we find an anti-theft device to locate your lost or stolen Android device, and even options to lock it remotely or directly delete the data on it. It is also possible to create a blacklist to block unwanted contacts who have used to disturb you.