This is very cool idea, but the whole thing gives me the impression that it was developed without customer feedback.

Is anyone using it? Group buying is something that can be done without any special tools. If people are already doing it, then there are probably group buying forums out there that could use your support in making them more efficient.

If people aren't already doing group buying, then the real work is in convincing people to do it! If you don't already have connections to merchants who are doing this, then you need to find them, or start doing it yourself.

I hope this works out for you, because it seems like an awesome idea. The app looks good, but comes across as being a technical tool, rather than something that generates sales.