When your game is ready to release you'll need a metric Butt Ton of images, icons, and banners that go everywhere so people on devices of all shapes and sizes can have a chance to see a pretty little image and give your game a try. Here's a look at the ones I made and a few tips on making your own quickly and easily.
I've made about 29 promotional images for TriGrid and that number increases with every new site I want to get featured on. Images submitted must be a certain pixel by pixel size and can usually be generalized into Small Square, Big Square, Horizontal Strip, Vertical Strip, Horizontal Rectangle, Vertical Rectangle, Horizontal Longtangle, and Vertical Longtanlge.
When it comes to images I use the basic 8 shapes for any banners and icons I might need and just re-scale them from a giant hi-res using Gimp (world's best free Photoshop clone).
|Splash (Launch) Screen|
That's just a few examples of what I mean. Get the basic images done and re-scaling them will be a lot easier than drawing 30+ unique images.