Two lines sold it!

All I needed to read was this one line, one line I had been looking for in other vault/protective apps but never found it until now! " all of your data in this app is stored only in YOUR device", "third party apps (like this one) are not allowed to delete photos or videos In the apple photo library"

J.breezee about A Vault Pic Private Photo Vault - Ultimate Private Picture Organizer Keep Your Snaps Safe Free