I downloaded Real Racing on my new Ipod Touch 4G and I realized I couldn't steer around. I tried an app called Gyroscope, but that also did not work. I played Doodle Jump and Mega Jump and those worked fine.
I was really confused at this point. I restored my Ipod Touch (from Itunes) completely and re-synced. Doodle Jump worked, but Gyroscope and Real Racing still did not work. I'm not sure if this is the app's problem, or if there is something wrong with my Ipod.
Does it go into Landscape mode (try Mail, Safari, Photos)? If it goes into Landscape mode, most likely it is an app issue. However, if it won't go into Landscape, plug it into iTunes and do a restore. Restoring is the only thing that I have found that will fix accelerometer problems.