Ridge Racer 3D is a direct port of the iOS version.
That said, you cant expect it to demonstrate the 3DS capabilities in any way, besides the fact that the stereoscopic 3D does add a superior sense of speed to the game if you compare both versions.
After over 40 hours in the game, I really can't say I didn't have fun playing this, because I did, but I also cant say I would buy it again at full price if I knew what it was like. The A.I. is ruthless, making you think that you are the main target of all the competitors, since all of them try to get a piece of you, sometimes all at once. And later on you'll see yourself cursing out loud often because of that last second defeat.
Start your engines