Boyfriend had tinder on his phone

We’ve been together for 3 years. I went through his phone and I’m not gonna bullshit and say “I was just trying to watch videos on his phone” I was going through his phone and there was nothing weird on there until I searched for Tinder and it was there. Yes I know I invaded his privacy. It wasn’t on the Home Screen. His excuse was that he must have deleted it from the home screen and not deleted the app altogether. The last messages he opened were from before we were dating and there were a few messages from other people after that that were never opened. The picture is also from before we were dating too. Would you believe him and give him another chance or is it obvious he’s lying about forgetting to delete it and just deleting it from the Home Screen

Edit: It’s not that I don’t believe him, the fact that it was inactive is reassuring i just don’t want to be dumb and over react or under react since it was just really shocking seeing it on his phone

Guys.. I don’t want to break up with him lol I love him and want to spend my life with him. would you guys not be a little bit shocked to find tinder on your boyfriend of 3 years phone? Not even a little bit?