When I look for flights, I check bing, kayak, orbitz as well as hipmunk. Which one do I prefer? Simple: the one that gives me the best fare. Unfortunately it ends up being a different one each time.
But on mobile https://market.android.com/details?id=com.hipmunk.android "This app is incompatible with your Play HTC HTC Wildfire.". Well, all other work, I don't see a reason why a form to search results via an api shouldn't work on ANY device.