When we first started dating he wouldn’t hide his phone.

When my bf and I first started dating we were open wouldn’t hide anything, would both use each others phones to play games or change music, knew the passwords and it was just open and nothing to hide. He cheated on me locked his phone wouldn’t let me go near it within 10 feet, and freaks out if I touch it. We broke up after he cheated but remained friends. What he did like trying to hide it from me and not just being honest with me still bothers me. We still hangout and see each other sometimes even though we’re not Dating. It bothers me that he hides his phone from me though as our relationship wasn’t based on hiding the phone, it was all open. Should I bring it up to him and ask him if we can be open with our phones? He’s mentioned he now feels like it’s an invasion of privacy. Should I just move on or see if he’s open to things being how they once were? How would I ask him about it or bring it up?