Flocks of birds are fascinating - now you can get them on your smartphone. This boid simulation uses three simple rules to form swarms. You can follow them with awe. * geometric figures or animated 2d birds * two different swarms * a hawk, the enemy of all boids * the water hole, as a rest for all * disturbance of the swarm with a touch * connect birds of a swarm * adjustable birds and background colors * use your own picture as background * automatic number of birds to get high performance * s