Generally to get a higher score in the game, memorize how to beat each of the games right away, first, and then you can begin concentrating on speed.
Tap with two fingers as often as possible, everywhere that it will help you complete the round faster.
During the Plane game if you just blow or go "ahhhhh" into the phone's microphone you'll beat the airplane round.
Swipe with four fingers all over the screen to beat the puke round.
To beat the balloon stage use more than one finger to drag a path from the base of the balloon to the hand. If you get enough practice, you can use three or four fingers at a time and swipe accurately.
To finish Pirahna stage press the pirahna and swipe away, like youre flicking it.
For Toaster and fork just lift the fork with your finger.