FlappyBee is a mobile game made with Unity3D. In it you will have to avoid to collide with the tree trunks as much as you can.
By default, the bee falls down (because of the gravity), for each touch in the screen it will impulse up itself with a certain force. That means it can be uset to slowly descend or, if you tap it fast, can result in a fast ascent with his consecuent inerthia.