Grand Theft Auto: Liberty City Stories is a classic game and a must have for any PSP Gamer.
What made GTA:LCS such a classic is all of the prior elements of the GTA Games for Consoles and PC have been packed into this Portable Device which makes the game exceedingly addicting while on the go.
There aren't many added features to the game besides the ability to acquire motorcycles.
A downfall to the game is the lack of multiplayer. Although the game has ad hoc, it lacks infrastructural play. Even the ability of downloading content via infrastructural would've been cool.
The bottom line is that this game is a classic compiled into the PSP for addicting gameplay. Really, the only thing I thought was missing from it was the online functions.