I have a multiplatform game (web/iOS/Android) in the making. In the free version the core game is still fully playable but people who choose to pay will get more social features (and no ads, of course).

I was thinking that rather than having a free and a paid version for all the platforms I may release the apps just for free and if the users want more, they have to register and pay a one-time fee (through a payment gateway or PayPal). The extra content would then be available in all the clients they have access to. Theoretically, this means a better value for the players and less maintenance and headache for me (obviously I have to handle all the payment troubles myself).

Does it fit into the business model of Apple/Google? Or will they still claim their share of the registration fee?