Use arrow keys to move and space to pass to next level, you need to arrive at the right edge, which has a white line. If you touch the red pterodactyls or the cactus, you´ve one life left, if you loose all the lives, you loose the game. Touch Play to begin. If you want the music on, just do not click the music button, but if you want it off, click the button.
Thanks to (I don´t remember who) for the pterodactyls. The other things I did myself, all the coding, the music and art. Idea was mine. Please if there are any glitches tell me in comments. My twentieth project shared!