If you want a fun app that can make cool stuff in seconds, the "Magic Marker" is probably an app you should check out. Magic marker lets you create new images or enhance existing ones with neon-bright colours you paint onto the screen with your finger tip. 
You can pick one of 7 pre-set colours or run your finger tip around a colour wheel to create a more subtle set of shades in between. To confirm the colour of your choice, you push the button in the middle of the wheel. You're then placed back in the main screen and you can begin painting.If you aren't happy with each finger stroke - or all of them - there are un-do and re-do buttons that appear to be able to handle a very large number of amendments.
You can paint on the default black canvas or choose any image on your phone to add your magic touch to.
When you have completed your masterpiece, you can save it to your phone or share it via whatever apps you have installed that allow sharing.My list included Twitter, Gmail, Facebook, Picasa, Picsay Pro (for further editing), Printershare (for printing locally or over the Internet)...and several others. The idea here is that you can do pretty much whatever you want with your image once you're done.
It would be great if you could magnify the image and be more precise, but as it is, Magic Marker lets you create or add some quick, impressionistic and colourful highlights with the swipe of a finger.
I like this one. See what you think. I think this app is free. On my phone it just says "installed". :-)
