How to effectively protect yourself from leakage of personal data when you lose your Android smartphone?

Question

Android

For example, one day I lose my android phone or it is stolen from me or confiscated.
I would like that in this case, the "new owner" could not read a single file from there (except, perhaps, the program code of the system kernel, which is not personalized in any way) or even see their (file) names (the same applies to the contents of the SD card) , not to mention read my mail or notes or, say, submit a Google+ post on my behalf.
What are the ways to achieve such security?
Whether he will be able to change the phone at the same time and use it like new, while he doesn’t really care, he can - and let, the main thing is that this use does not affect me in any way.

Answer 1

Change all passwords of your accounts
starting with google, or install a dedicated hard drive formatting chip)

Answer 2

You can use the native Google service: https://www.google.com/android/devicemanager?hl=ru. Features: find on the map, format, block. Other services require root rights for normal operation. If they are, then I can offer Avast as a free tool. With it, even a factory reset via Recovery will not help.

Answer 3

You can recommend changing the hardware platform. Of course, in the event that you are not already the owner of the solutions below.
For example, look towards " Boeing Black " or " Blackphone ".
In this case, you will need to take into account the laws of your country of residence - regarding the use of hardware encryption. Not only data, but mostly voice. Not everywhere your desire for privacy will be adequately understood :)
In general, this seems to be a trend.

Answer 4

look towards preyproject.com?
(does not require root, protected from deletion by a user who does not know a separate password (registered as device admin), can be activated via SMS)