Well I just recently discovered that he didn't delete the dating app and it upsets me. I told him that I felt uncomfortable with the dating app still being on his phone when he was the one to say he wanted to see where things go for us. He said I'm the only one he talks to and that he doesn't talk to any women on the app. He said that if he gets a notification he'll check it out but he won't respond. No matter how much I told that it made me feel insecure and uncomfortable he still won't delete the app off of his phone. 

I have a problem with this because my ex fiancé used his phone to cheat on me behind my back for a month. This guy I'm seeing knows about me being previously engaged and that I was cheated on. I know that my ex fiancé and this guy are completely different people, but since being cheated on I have issues trusting guys when I know they have a dating app on their phone while they're still seeing me. 

Am I getting to worked up over nothing or do I have a reason to feel insecure and uncomfortable?