There was a shocking article by Joanna Stern of the Wall Street Journal about how you are a simple bar trick away from losing access to all your photos (and some money) forever. All they need to do is steal your iPhone after seeing you type in your passcode, and they can lock you out of your account forever. 1. This is why we back up stuff and 2. There is a way to stop this. I'm not yet sure how vulnerable Android folks are to the same problem. If I've piqued your interest, this is the episode for you.
Here are two YouTube videos where the WSJ talks about this:
https://www.youtube.com/watch?v=QUYODQB_2wQ
https://www.youtube.com/watch?v=tCfb9Wizq9Q