It that possible for the wallpaper cache saved in Android /data folder being hacked? (Not Rooted) My boyfriend was kidding with me, setting my private photo as wallpaper.

I deleted the photo but the wallpaper still remains there...

After browsing through some information on the net, I found out that the wallpaper is saved to a folder which only can be accessed after rooting.

If I change the wallpaper, will the previous wallpaper automatically be deleted?

If not, since it is saving in a folder which only can be accessed after rooting, is it safe? Or does it still have a possibility of being hacked by others?
If you'd like to be safe, you could always wipe the cache of the phone:


1. Turn off your Galaxy S3.
2. Hold down the Home and Volume Up keys.
3. Press and hold the Power button while still holding the other keys
4. As soon as you see the Samsung logo, release all keys/buttons.
5. Press on the Volume Down key to tab down to “wipe cache partition”
6. Once it is highlighted, press the Power button to select it.
7. On the next page, Press the Volume down button to highlight "yes" and press the
   Power button to select it.
8. Wait for a few seconds for the phone to clear the data.
9. Press the Power button on the next page to select “reboot system now.”
10.Wait for your phone to reboot.

  
  *This will not wipe any of your information stored on phone, pictures, video's, apps, contacts, etc. will all be safe


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