Reputation: 100438
I want to use in-app billing to implement virtual money: a user can for example buy sets of 50, 100 and 250 coins.
I'm wondering how I would manage the number of coins each user has. Do I have to manage that myself or does Android provide something for this? If not, how would I store this information? UID won't work if the user has multiple devices, but I'd prefer not to store email-addresses.
Any thoughts on this matter?
Upvotes: 1
Views: 301
Reputation: 82563
What I do is have the data stored on a server and access it through a Web service. I initially stored it locally, but quite a few rooted users started editing the app data and getting extra money.
Essentially, I use in app purchases to have the user pay. When I receive confirmation that the transaction was successful, I send a pre defined string to my server. I don't send raw numeric values like 50 as a user could then make it 500 and get extra cash. Instead, the server matches the string it receives with a list of strings. If there is a match, it adds that much money to the user's account. If there isn't a match, it tells the app there was an error.
Upvotes: 1