You are going to be tempted to save money, and one way to do that is to make your own graphics. Everyone thinks they can do this themselves, but only a select few are good at it. The intersecting portion of the venn diagram of coders and graphic designers is relatively small, so be careful not to delude yourself into thinking you belong there when you don’t. Even if you are pretty good, I recommend treading lightly here. Your time is probably not best spent creating the graphics for your app icon and your feature graphic, especially if it is not going to look professionally done. If you’re not 100% confident that you are going to nail it, or if you don’t have the time (trust me, you don’t), outsource your graphic design. Use a site like 99designs for something professional or something like Fiverr for something quick and passable.
Getting Started With Android 