This app should be 5 stars. It's a lot of fun. The problem is that the app is buggy and when a level has a bug you cannot move forward, so you can no longer use the app. Two times now I have encountered a bug that has prevented me from using the app. The developer recently fixed bugs, but there is currently still a bug in level 31. So, once you get to level 31 you can NOT use the app any more. I understand that there can be bugs in an app, but with this app a bug makes the entire app worthless from that level onward (because you cannot advance to the next level until you complete the previous level - which can be made impossible if there is a bug). It would be good to include an option to skip a level so if any given level has a bug you could just skip it and continue to use the app. Please either fix all bugs or add an option to skip a level. Then the app would be 5 stars.