I don't know how many people have suggested this, but I personally think that spiral knights would be great as an app. It would open up the game to an entire new group of people. I don't design apps or anything (I just play them) I don't know if it would work, again, just a suggestion.
I do agree that SK would work great as a mobile game given that all you really need is a way to move and a shoot button (and a few other things but you get the idea), but that'd probably involve pretty much programming the whole game again from scratch (since I'm pretty sure that mobile phones don't run Java).