Need advice for creating an app

My username at gmail, I'll see what I can do.

This could go very poorly for you.

You should work on an NDA for any material you distribute.

You watch too many movies. What is the NDA going to protect? It sounds like there is no IP at this point, that's what he's looking to get someone to create. You can't legally protect an abstract idea. App ideas are a penny a dozen and software devs would rather make money building it for you than try to steal it hoping it's the next Facebook. It takes a pretty decent amount of money to get an app going. From cost of creation to the much higher cost of promotion. I guarantee whoever you share your app idea with is nowhere near as anxious to spend that kind of money on your idea as you are. Speaking of, if you are worried about someone stealing your idea, don't create an app. If it is successful thousands will try to imitate it. If you have an original idea, and it catches on, the best you can hope for is that your head start and continued development based on the needs of your users is enough to hold off the competition or cash out early. None of the current billion dollars apps were original ideas they are just someone who came along and did it better. The OP asked what is the next step. You have to be pretty comfortable with the concept you are going to be talking to devs, probably more than one if you are shopping pricing, and putting your abstract idea out there without any protection other than it doesn't sound brilliant enough, yet and maybe ever, to steal.

The brutally honest truth is that your app idea fricking sucks and you do not have enough capital or marketing $$$ to make it be successful.