There are 9 stages, ordered by difficulty, But you can play at any stage. A button at right bottom corner is to make a shot. A seekbar is to change the power of stroke. By touching the screen, the direction of stroke is changed. Black dot lines indicate trajectories of the cue ball. A red dot line indicates the trajectory of the target ball, after a collision with a cue ball. If the stage is cleared, the menu button is marked as so. You have 180 seconds for each stage. Please enjoy!! I am writing a blog. (Have a cup of coffee? http://try.candypop.jp/nice) I wrote about this project in the following article. (http://try.candypop.jp/nice/blog/android/3d-billiards-practice-is-out/) If you have interests about how I made this game, please read my blog, too.