Marble Blast Ultra

Take your time. For every single level with alot of gems and checkpoints, simply collect a gem and then get a checkpoint before looking for the next one, if you fall off you won't have to get the gem over again. Level 60 "Schadenfreude" is one of the levels that you're going to spend minutes on the first time around. I spent over 10 minutes trying to complete it the first time but only after a couple of more tries I hit the par time. Now my best is 27 seconds, so if you're struggling with levels, just keep trying.

I assume the hardest would probably be the levels with the moving platforms. For these you should try to memorize when to jump and where to move. For the giant cubes come towards you, to avoid them you'll have to be out of their way when they pass the platform. If this seems to be a problem you could experiment with the "start glitch". Pause the game while your marble is still in the white beam in the beginning and wait for some seconds then continue. You'll spawn earlier making the pattern a little different and possibly slightly easier.