Let fly farther Birdman.
Birdman can rise by tapping, but he consumes his power.
If Birdman rides on the wind, he can rise without exhausting his power.
When Birdman hits an obstacle, he will exhaust his power at once.
A balloon appears when you clear the quota, and it is a chance to revive his power.
He falls into the sea when his power is zero, and it will be game over.
This game corresponds to the net ranking, so you can compete with rivals in the world.