A game that meets the requirements of the project well, single control, and super easy to pick up. However, provides a level of complexity that means that the game naturally gets harder as you progress, nice touch.
Firstly, is the way you have exported the game the most efficient or user friendly method of doing so? Perhaps there is an even more accessible way of playing it? Secondly, its a bit difficult to tell where your bullet is, and some feedback when hitting a target (like a small sprite) would improve user experience.
On the whole, not much to complain about with some room to really improve the uniqueness. Perhaps a range of different targets, with different attributes. For this submission, however, this is more than enough. Good job.