Microsoft has revealed that its plans to support in-app purchasing on Windows Phone will be limited to its upcoming version 8 release. In MSDN documentation, the software maker advises developers that you can only add in-app products to Windows Phone 8 apps. The revelation isn't surprising as Microsoft plans to manage in-app purchases via its new Wallet Hub in Windows Phone 8. The confirmation of a lack of in-app purchasing for the Windows Phone 7.8 update appears to suggest that existing devices will miss out on the Wallet Hub functionality too.

Microsoft discussed its Wallet Hub in detail at a Windows Phone Summit in June, including its support for NFC, contactless payments, deals, loyalty cards, in-app purchases, and credit and debit cards. Although existing Windows Phone users will get a 7.8 update, that includes the new Start Screen, a lot of other features are still relatively unknown. We've reached out to Microsoft to confirm whether the lack of in-app purchasing in Windows Phone 7.8 means Wallet isn't supported — we'll update you accordingly.

Thanks, Thomas!