<human>: Can you succinctly summarize the text in 1-3 sentences?

This one's pretty simple.

I met my wonderful bf on Tinder and we became official after a month or so, 5 months ago. I was in bed with him a few weeks ago and we were watching funny videos on his phone. When he went to his home page at one point, I saw the Tinder app. 

Now I kept Tinder on my phone too for a couple months after we were official, but I had turned off the "discovery" option which doesn't show your profile and you can't swipe, but you still have access to all your messages. I did this because we talking on Tinder for a surprisingly long time before switching to text, and the convos were great. I'd sometimes consult back to it when I wanted to remember a detail that he previously mentioned. 

Well I thought I should probably delete the app all together since we are official. Didn't want him or anyone to see it and think I was still using it. He could most definitely have the app still because of the same reasons but how can I be certain?

We get into long intellectual debates frequently and one time we were discussing cheating and he evidently has very strong morals and would never cheat. His distaste for it and anyone who does it was clear. But that tiny part of my brain is thinking, what if he doesn't consider talking to girls as cheating?

Anyway, my question is very simple and I know I'm probably making this a bigger deal that it needs to me. How can I ask him why he still has it on his phone, in the most non-accusatory way? Kind of like, hey out of curiosity, not hey I wonder if you're talking to other girls behind my back. Because it very well could be he likes reading through our old convos?
<bot>: How would you like to be asked why you still have Tinder on your phone despite being in a relationship, that wouldn't make you feel defensive or not trusted?