How do I permanently delete everything on my Samsung S4 Active?

[AC Question]

how to really permanently delete everything on samsung s4 active?

I will give my phone to technical service due to a problem on battery. I am a little paranoid about technical service employee and don't trust them in terms of personal privacy.

I read that factory reset does not permanently remove everything on phone.

I would like to delete everything on phone in a way that in which even high level forensic recovery softwares can't recover anything.

By the way, i am not an expert user on android so please describe the solution in detailed form.

 

[SpookDroid]

Re: how to really permanently delete everything on samsung s4 active?

Factory Reset or Data Wipes do delete your info from the phone, but yeah, not to a low level (they only mask away the data, but the actual data is still there, waiting to be overwritten by new data).

There are tools out there to wipe it out for good, but basically, what you need to do is overwrite said data. If you have a 32GB drive, write 32GB worth of junk files into it, then delete it. That effectively makes your old data inaccessible even after a data wipe.

 

[Rukbat]

Re: how to really permanently delete everything on samsung s4 active?

There's no way short of physical destruction by high heat (around 2,580 degrees F, the melting point of silicon) to prevent forensic recovery of data on the type of memory used in phones. Can a repair tech use that type of recovery? Sure, if he wants free room and board for the next 20 years (or more) on the federal government's tab. No reputable repair shop would allow an employee to even have the needed equipment in the shop. (Having it would be the same as possession of burglar tools, and to prevent being sued by some customer - which would bring the feds into the case - the owner would turn the tech over to the feds himself. I say this as the past owner of a few cellphone repair facilities.) The normal repair is reflashing the ROM or replacing parts - and that uses stuff that couldn't come close to reading the data on a factory reset phone.

About the only thing you can really delete would be the internal SD card, and there are data files all over the phone not on the card. If you're really paranoid (the tinfoil over every window type), hire a Linux nerd to find all the app databases and write junk to them. That's where most of "your" data is. SQLite is trivial to insert data into. (The ultimate paranoid solution is to use dd to write random data to the phone several times, but that would probably do to your warranty what the Godzilla did to Japan - not just void it but totally devastate it.)