For each purchase in Evermotion Shop you get a small amount of Virtual Cash that you can spend for your next purchases.
Virtual Cash expires one year after the last purchase made with real money or mix of real money and virtual cash. So, if you are afraid that your Virtual Cash expires, please make a purchase (any purchase) with the real cash, your virtual cash will be valid for one year more.
You can use Virtual Cash during checkout. Here is a screenshot of a process:
