Sketchy

So my boyfriend always accuses me of cheating though I never have. He had though, smh. Anyway, somehow he always knows my activity on my phone. I have nothing to hide & I let him look @ my phone anytime that he wants. But he knows what sites I've been on, messages I've sent, requests I've made (friend requests). Does anyone have any idea how he is finding out all of this? I believe somehow he has hacked my phone but I can't figure out how. I don't appreciate it, especially since he is so secretive with his phone. How could he be seeing everything? And this is when we are not together. I'd appreciate any ideas.