I have made a very primitive app prototype. I am looking for users that would be interested in taking a look and giving me some feedback. Contact me and I can sent you an invite to the justinmind prototyper.
I'd give a bit more info if I was you. Like the type of thing it's useful for, or the problem it's aiming to solve. That should help you get people who are in the space you're aiming at to look at it