Overview: Overall I'm pleased with the result, they fit in nicely on the iphone to your left, apart from the text on 3 of them (but I suppose if you like a symbol you will zoom in). If I put more spare time on them or chose a different symbol, some could have been more detailed or refined, however that detail would have been lost when they are shortened.
I really like how this icon turned out, up close that is, on the Iphone when it is small at a "distance" the icon is a bit dark so even though its easier to make out the next on this one than the others, its hard to make out the entire icon. So maybe lighting it up abit would help visibility on the small screen.
I changed from a darken background on this one after learning from the icon above - After scanning and copying the actually UFO itself, I added some effects to it, to add the shine and glow; again another simple icon, that i think works. However the black lines below the UFO were meant to simulate it moving, but that hasnt quite worked.
This is probably the simplest of my designs, when i started it was hard to get all the shapes together into teeth and there were loads of gaps making it look untidy; however I went other the sides in what looks like gums of whatever mouth, and its turned out well. Im not 100% with the teeth but they look fine.
Finally my fantasy icon, the only one without text, again I think this one came out well, I chose to scan this rather than draw it out in photoshop (which looked quite bad) and It has turned out alright, very basic and with some added effects it looks decent from the Iphone view. I would maybe change a couple of colours like the grey of the shield, or make it seem shiny'er.
