The function you want to provide is quite simple, implementing an "app for x" search engine, so i guess you should focus on that and try to provide something really user friendly. I suggest a few things:

-Improve graphics a lot: Nice theme, Icons, highlighted prices and why not a small preview screenshot directly in the search results so that i don't need to open all the app singularly?

-Reduce results. If i'm searching an app and you simply return all the google market results why shouldn't i use the market directly?

You should calculate your own results based on vote/downloads/manual_pick and maybe highlight new apps(that may be worthwhile but have still not enough votes/downloads).

- Make it easy to download, QR-Code easily accessible.