When selling your iphone, is the data wipe safe?

[Italianblend]

What I mean is, if I sell my 4S back to apple, and use the "erase all content and settings," how secure is that really? I mean, when you sell a computer they tell you do do a couple of erasures of the hard drive so that nobody can extract information from it. This is literally a 10 second erasure of your data.

 

[user-name-here]

What I mean is, if I sell my 4S back to apple, and use the "erase all content and settings," how secure is that really? I mean, when you sell a computer they tell you do do a couple of erasures of the hard drive so that nobody can extract information from it. This is literally a 10 second erasure of your data.

If you're worried you can always "erase all content and settings", then set it up as a new phone and repeat the process as many times as you like until you feel comfortable.

 

[evilrt]

Take out the SIM card.

 

[Rigby]

What I mean is, if I sell my 4S back to apple, and use the "erase all content and settings," how secure is that really? I mean, when you sell a computer they tell you do do a couple of erasures of the hard drive so that nobody can extract information from it. This is literally a 10 second erasure of your data.

It is secure since hardware-assisted data protection was introduced with iPhone 4 (or was it 3GS?). All data is automatically encrypted before writing it to flash. When you do an erase, the phone just deletes the encryption keys (this is why it is so fast). Even if someone manages to extract any remaining data from the flash memory, it is useless without the keys.