My favorites on the iCade:
Blazing star
R-Type II
Pix 'n Rush DX
Vectrex
Wacoon Jump!
Danmaku U2
Speedrun
League of evil series
Metal slug
Metal Slug X
Gridrunner
Storm strikers
Plasma Sky
Abyss attack
Shogun
Shmup
Huge list :
http://forums.toucharcade.com/showthread.php?t=96023
Have fun !
Thanks for the list! Turned out to be pretty helpful. I'm really digging a bunch of the games you recomended. Especially Abyss Attack, Danmaku Unlimited 1&2, Gridrunner, and Plasma Sky. I'm going to concentrate on Vertical games mostly for now since my case sucks and to get my ipad out would probably break it. So when I get a new case, I'll get more horizontal shooters and beatem ups....Well I did buy R-type II, but it was only two bucks. I would've got Blazing Star too, but I already own it on MVS and my phone.
On a sidenote: WHY THE HELL WON'T CAVE MAKE THEIR GAMES SUPPORT ICADE??!!! I'd buy at least two of their games (probably more) if they added Icade support. I really hope they change this. Sure playing a shooter while dragging your finger isn't the worst thing ever, but it's much better to have the option for a controller. Especially with Icade and other bluetooth controllers getting more popular.