Checking a user has purchased an app

Question

I created two apps one free and one PRO and published them to the market, now in hindsight I should have taken the time to create an In-App-Billing element to unlock the free to the full. I wish to go ahead anyway and create the in-app billing element in the free version, and then remove the other (PRO) version from the market.

My issue though is how do I determine that a user who installs the free version has previously installed the PRO version and hence auto unlock it?

Assuming they removed the PRO app already from their device, can I access their purchased transactions and then unlock that way?

Otherwise is there a way in the dev console to create a transaction for them without them paying, and when they load the free version, it will restore that transaction?

I didn't use LVL in the PRO version, does that make a difference?

Answer 1

There is no support for this currently. You can check whether a user has bought a paid app using the licensing service (LVL), but it cannot be used in a paid app. You obviously can't create in-app transactions (Google handles this), and IAB has no native support for cupons/activation codes. You can either:

• build your own coupon/activation service (requires a server), or
• manually refund the IAB purchase for users who have already bought the pro one. You will lose the 30% Google fee in this case though.