Tried it on a Motorola Defy, it was pretty good, actually much harder that what it looked like.
One gameplay suggestion:
- Being able to go free fall, just stop "flying" and just fall when not touching the screen, that way it would feel more like a bird flying, and not so much as a spaceship ignoring gravity. Also, I felt there should be more of a "constraint" when going directly upwards, it just keeps going up until it hits the roof, and feels pretty unrealistic, maybe it could stop ascending and start a descend, like planes do in most games. (not like there's that much air space when playing on a small phone, but its an idea)
- The pace of the game also tends to get a bit slow, its hard to aim the targets so you tend to keep flying a lot and turning around. Of course, after some practice, that gets better, but the first levels get pretty hard as you get used to the controls.
Apart from that, great graphics, music is outstanding, and the birds/animals/pos-apocalyptic "theme" is great
Congratulations for the work!