[Q] Erase EVERYTHING + extra question

Hello,

Is there a way to completely ERASE EVERY bit of USER DATA? A factory reset seems to leave different bits of information and doesn't really erase everything. Does flashing a stock ROM via Odin erase everything completely?

Extra question: Does the mid-bezel (frame) include the little bit of plastic under the camera? Mine is all scratched up (the silver paint is literally gone) and I'm wondering if that can be replaced.

Before i forget! (how to bypass and erase the new security in android 5.1.1 )

Sorry for my english, im very excited and i want to share this because i dont know exactly what i did.

Guys i found a way to pass the android security (gmail account), I dont remember all the steps because i spent hours and hours but the trick is :
1.- Recieve a call in the first screen
2.- Try to save that contact
3.- Choose an "exchange account" (add any - NO GMAIL-)
4.- Try to share that contact
5.- Choose the exchange account previously created
6.- It will be opened the gmail app
7.- There go to settings
8.- Choose "general configuration"
9.- Wala! General settings will be prompted
10.- Activate developer options and disable OEM UNLOCK
11.- Go to fastboot and type fastboot oem unlock
12.- Thats all!!!!!!!

Erase Facebook and Instagram

Anyone know of a way to erase them from the phone? It's annoying they baked them into the phone and you can't use greenify or Moboclean on them. They are usually on my top list for the battery graph stats. I am not rooted so I'm sure my chances are slim. Any help would be grateful.

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