Does this count as cheating?

Pls be nice bc some of y’all can be really mean, and I’m really hurt right now. Me and my boyfriend have been together 2 years, and the past few months have been rocky, and a lot of it has to do with the miscarriage we went through roughly 6 mo. ago. After it happened, our relationship has really gone downhill, but we kept saying how we wanted to keep trying bc we love each other, blah blah blah.

Okay so at the beginning of our relationship, I found some pictures of some females in his phone, and in some, he was w the girls too, but I let it go. We hadn’t been together that long and I didn’t want to come off as crazy, BUT his story was a little fishy, but, I let it go. Ever since then, I’ve been super jealous and have always secretly checked his phone and never found anything, so I figured that sort of behavior was in the past. Anyways a few weeks ago we got into it really bad and I wanted to move out bc I was fed up, but again, we both were like, ‘let’s just stay together’ but the fight was serious and we’ve been really moody toward each other.

Then, and here’s what I’m asking about, today, I went through his phone bc he came home acting weird, and kind of distant. He was being short and rude and just not like how he normally is. and I found this dating app called Down on it, which is supposed to be used for hookups and shit. It hasn’t ever been used bc it was like ‘make an account, when I opened it, But now it makes me wonder if he ever used any other dating apps? I asked him about it and he seriously looked at me and was like ‘baby I didn’t use it bc it doesn’t work’ and I started crying telling him that he downloaded it for a reason, and he actually got angry with me and told me to leave him alone. (We live together and have a spare bedroom so I went in there) and now I’m sitting here thinking, ‘is this cheating’