[Q] How to REALLY wipe an Android Device?

[Ms.O]

so i've seen news stories about how the standard "remove sim and sd card; factory reset; encrypt; factory reset; encrypt; factory reset" on a phone still doesn't totally remove all of your data from the phone.

does anyone know how to do this for real? so that ALL of your data is erased? i want to trade my galaxy note 3 in for a note 4, but am super paranoid about this (and i'm still hanging onto my old galaxy note 1 for the same reason).

any and all replies welcomed! thanks!

ps. i have a galaxy note 3, android 4.4.2

 

[nagalun]

Boot into recovery, and connect the USB cable to your PC,
then with adb shell do this command with root:

umount /dev/block/platform/dw_mmc.0/by-name/USERDATA
dd if=/dev/replacethis bs=4M of=/dev/block/platform/dw_mmc.0/by-name/USERDATA
sync

Where "replacethis" you can put zero, which zeroes all of the information on the device, or urandom, which fills up the data partition with random garbage data.
Both are very secure, and should do urandom if you're very paranoid..
After completing that command you should format it so the partition is usable again.
You can do the same thing with system and cache (system should not matter anyway, its read only unless you modified it.)

 

[Ms.O]

thanks for your reply. most of it was over my head, cuz I didn't understand much of it.

I may play around with my note 1 to see if I can figure out how to do what you said.

thank you. ?

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