Many users ask about in-app purchases.
Some of the questions and concerns are:
I previously purchased a pack and now it is locked
This can happen if they move to a new device. The solution is to use the "Restore Purchases" button on the pages screen. This will reprocesses their previous app store transactions and unlock packs they have bought.
Do I have to buy the pack again?
No. In fact, the types of in-app purchases used in colAR Mix cannot be purchased more than once by the same account. Google calls them "managed" products and Apple calls them "Non-Consumable" purchases. Each store associates the purchase with your account and will not let a second purchase of the same product occur. If a user attempts to buy the same product again, the store will alert them that they already own it and the transaction will go through successfully but at zero cost to the user.
Can I get a refund?
A refund is possible, but it is not a developer issue, it is an app store issue. As the previous item explains, the purchase is registered against the user's account. In order to get a refund for that purchase the user needs to contact the appropriate app store with the order number for the transaction.
A good reference for this process on iOS: http://www.macworld.com/article/2140066/how-to-get-an-app-store-refund-for-kids-accidental-in-app-purchases.html
Google Play: https://support.google.com/googleplay/answer/1050566?hl=en
Can I use Volume Purchasing?
This is currently not possible. colAR Mix uses in-app purchases which aren't covered by the volume purchasing program.