| RolStoppable said: The games required to sell handhelds are Nintendo games (and Monster Hunter, only in Japan though). You either have them or you don't. |
According to VGChartz data it would seem that the PSP suffered from a lack of Adventure, Rhythm/Music, Platformers, Simulation and Puzzle games when compared with the DS. As people say the DS had more portable games than the DS I will assume that games of those genre must be what people are referring to when they say portable games.
When comparing the number of titles on each handheld that sold over 1 million copies we have a ratio similar to that of the hardware sales of the machines themselves. This leads me to believe that it is actually having a well rounded library and having multiple examples of a quality titles within any given genre that is central to success.
I do think Nintendo's IP benefit them greatly but that they aren't the only games that can sell handhelds.
