There probably is no tutorial to do this Ivy. This will be a complex app. What have you
Do you have a lot of experience with App Inventor? You are going to have to know how to use an online database to store transactions, how to create user log in credentials and a way to verify them, Do you have a diagram showing how you think this should work?
How do you get started? What you do depends on what you know now.
Here are some resources to help you learn to use the AI2 tools A very good way to learn App Inventor is to read the free Inventor's Manual here in the AI2 free online eBook http://www.appinventor.org/book2
... the links are at the bottom of the Web page. The book 'teaches' users how to program with AI2 blocks.
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