Can anyone give some technical insight on what this ominous "Device data encryption" and "memory card encryption" uses under the hood? dm-crypt, maybe? i'm completely new to Android and naturally want a phone with encryption so a thief cannot steal my data. How is the encryption passphrase entered, and when? When starting up the phone, or do I have to enter it for unlocking the phone? Does it slow down things greatly, or just drain some battery life but that's it? I've searched the whole web on how this encryption works but wasn't able to find *anything*.