[Q] Extra Security for my Galaxy S6 Edge

I live in Venezuela, one of the most dangerous countries in the world - safety regarded, if not, the most unsafe.
I have been sporting my GS6 Edge without any problem but i don't know when i can be the subject of a gunpoint theft, kidnap, common theft etc.

I wish to do an extreme makeover of my S6 Edge security settings. I have the fingerprint scanner but i do wish to have extra security level. Such as when i open certain app, it prompts me for a particular password. Yes, i'm willing to input a password every time i open certain applications in my phone....

Is there anything as it? That i can download and ask me a password for gmail, whatsapp,bbm... etc. Gallery......

I'm not rooted, and have never clicked on the Encrypt device thing, what does it does? Can i see a video? Can i de-encrypt in case i do not like the encrypt option? I need ideas for a better security than the fingerprint. If a thief gets my phone he might be able to see my personal info/family things. etc.

Also. 2. What are the better options for remote wipping, locate my GS6 etc. I just need to pay more attention to my devices security. Better be cautious than sorry.

Thanks folks!