Apple and Google Stores Software

Hi, I have products that I want to sell on Apple and Google Store through an application. The application will be free to download and users will be able to buy products through this application. The products are videos about EFT. Each product is a program with a collection of videos. A user purchasing the program will then unlock it from the applications gallery and be able to either watch the videos from the gallery or download them to their tablet or smartphone. The programs are located at [login to view URL] I am not familiar with how things will be placed or how this job will be done so I am open to information and feel free to ask me any questions. Let me know about the procedure from start to end about costs or any other needs for such implementation. Make sure to give me examples of applications you already may created for the stores.