Serious privacy concern.

I just had my phone serviced as I needed the screen replaced. When receiving my phone (which was already turned on), as soon as I had unlocked it, the phone gallery was open and the user had scrolled half way through my gallery. Additionally, when looking to see what apps were opened, my authenticator app was also open (which I have not used in months, and I know for certain was not me as I always end all app processes after using them because in slightly OCD). This is a serious privacy concern.