Game play on youtube: Youtube.com
Some of the comments of people who have played a game:
"I don't normally write reviews, but when I do I give it five stars. I love this game so much. I doesn't ask you to buy things to complete levels, isn't too hard or too easy, and it is just simply amazing!"
"It's never been easy to be a Ninja, it's the same in this game :) Cool obstacles, easy to control, but you need a good timing and fast reflexes. Graphic is very pleasant, you can play and relax"
"Nice game in which you should be really fast. Try to consentrate and tap fast to play it. Great idea which deserve high rates. Respect to developers"
GravityNinja is highly addictive game and you'll love it, so try not to break you device.
Tap will change you gravity and make you run the upper road, tap again and you're on bottom road. You can even change gravity in fly. Just make sure you dont hit an obstacle.
Good luck and have fun!