Guide for Rolling Sky for Android
There are actually five different levels in this game, and despite what it may look like, all five of them are available to you immediately. You do not need to beat a level in order to unlock the next level. Simply back out of a level, go to the level select screen, pick one of the five levels, and tap it.
In the case of some of the more difficult levels, such as level five, the obstacles consist more of a visual trickery than actual roadblocks. Watch the pattern of the various surfaces and objects on each level and you will easily be able to figure out where you can move to in order to avoid them and get far, eventually making it to 100% on each level.