There's a lot of portable games that are stylus/touch-driven. Kid Icarus came with a cradle for the 3DS and if he likes RPGs the recent Final Fantasy Theatrhyth

There's a lot of portable games that are stylus/touch-driven. Kid Icarus came with a cradle for the 3DS and if he likes RPGs the recent Final Fantasy Theatrhythm would work great. It supports a one-handed mode for the buttons too.