Recently an Oregon State Police detective confirmed to Jonathon Zdziarski that an OTB refurbished iPhone he purchased contained recoverable personal data. Zdziarski writes, While the restore process takes long enough to make most people assume the disk stored in NAND memory is formatted, it actually isnt.
MacsimumNews has compiled a list of suggested procedures to securely erase the iPhone. Here are the 7 suggestions:
1. Change passwords for all mail accounts that are synced to the iPhone or touch.
2. Make sure the device can no longer open the mail accounts.
3. Do an erase/restore of the iPhone or iPod touch, preferably using another computer or at least another account than the one the device was synced with.
4. Sync as many songs/videos of a non-compromising nature and nothing else to the newly restored device as will fit.
5. A good tool I recommend using to fill the drive up with data (songs/videos), is PhoneView. You can directly access the disk on your iPhone to totally fill it up.
6. After you have filled the drive up, do another erase/restore.
7. Repeat steps 4/5 with different content and erase/restore again. The more times you do this, the more times the data will be overwritten, thus having a less chance of recovery.
Once well confirmed or an official procedure is released we will post a step by step guide. Until then you may want to follow some of these suggestions to ensure the security of your data.