Mobile adaptations of music games have been surprisingly effective, despite lacking the tacky plastic controllers of their console-based bigger brothers.
But the scope of these games, such as the Guitar Hero franchise, is beginning to look quite limited. Other than adding new tracks (or a plastic clarinet, or tuba controller) there's not much further these games can go.
Fortunately, Guitar Hero World Tour doesn't make the mistake of trying. Instead, it simply makes a decent effort to refine what we've already seen, and that's actually no bad thing.