Gather Gems
You can gather gems as you advance, and they serve as your in-game currency. You'll want to snag as many of them as you can. When you finally make an error that ends your current run, you'll also be offered teh chance to watch a video ad, with still more coins waiting on the other side as a reward.
Mind the Shadow
As you progress, it can be difficult to tell where you can safely tap in order to keep things going. Watch for the ball's shadow, though, and you'll be fine. Make sure to tap while the shadow is positioned as close to the middle of the platform as possible, so that any minor timing errors don't morph into disasters.
Think About Aesthetics
The game requires some intense concentration, and you'll do best if you're comfortable with the action on-screen. You can change brightness settings by tapping the icon that looks like a lightbulb on the menu screen, and you can also adjust the color of the ball with in-game purchases using the gems you gather. Your choice of color can make it easier to see the helpful shadow... or more difficult. Try for fairly neutral color tones if you want the easiest time of things.