ipad app data persistant AFTER "erase all contents and settings" why ?

[jaxxxx]

i downloaded a video throught an ipad applications web browser and deleted the video and the application. i then did "erase all contents and settings". then reinstalled application. the video somehow remained in memory as i could access it without downloading it again. how does this persistent data remain memory ?

 

[dhewson777]

Did you restore after the erase?

 

[jaxxxx]

no restore after erase. i do not back up any app data with itunes or icloud. the only reason i thought of was the RAM memory flushed the contents of the video to flash memory when ipad shut down. then on reboot the system reloaded the video contents back into RAM before wiping the file system keys and recreating new keys.

 

[willerz2]

Never use the "Erase all contents and Settings" in the Settings.app. It brings out more problems than solutions from my experience. If you ever want to wipe a device, use iTunes to DFU restore the device. It might be that the video is stored in a part of the system files that the erase all contents and settings does not reach, mostly the core system folders.