Not the most creative or original idea, but quite well implemented! It's just as fun as the original Flappy Bird, so not much to say there- however, I think it would be helpful to disable to the collider for the birds after they pass half the width of the pipes, because once they are past the player's focus needs to shift to the next bird (something that isn't a part of the original Flappy Bird)! Overall though, very well made game, so good job :D