Here are the top 10 FREE apps for the photographer in you. (If you are using an Android phone)
Has lotsa of effects and filter. Comes with tiltshift mode too.
Polarioid style pics
Some lomo filters for you. You have to load photos from the library though
A World Of Photo
Social photo game.
Burst camera for you to capture sequence of action.
I think the name has already explained itself. Hehe.
Mix and match effects to creating stunning photos.
Adds vignette to your photos.
Has lots of effects for your photos.
Has interchangeable camera and film effects. Good looking app.
OK thats it. Enjoy!