Is this plagiarism or competition?
ars: I would email him again saying: "I had exactly that idea myself, and I see that you did too. I really want to implement it. Are you sure we can not collaborate? Because I really want to do this and if we can't collaborate I will go it alone."Emailing him in the first place was a bad idea, because he has more ammunition to claim you copied him. But you did it already, so you might as well go all the way.