XL Axiata on Tuesday officially announced support for carrier billing for Indonesian Windows Phone Store, the first to be introduced in Asia Pacific. As we reported last week, this feature allows Windows Phone users to purchase apps and games using their phone credits. However, what was not known last week was that this is an exclusive feature to Nokia Lumia phones, which means that other Windows Phones need not apply.

President director of Nokia Indonesia Martin Chirotarrab said in a statement, “a practical and trusted purchase method is key for consumers to be able to enjoy content and paid apps on Nokia Lumia, including various locally created apps. The introduction of carrier billing facility is the first in Asia Pacific for Windows Phone and therefore a significant and innovative leap for Nokia Indonesia

Maretha Dewi, Nokia Indonesia head of developer experience, said on stage that Nokia had observed over time that Indonesians tend to purchase apps if they are allowed to try the app before buying and the lack of credit card adoption had made this a difficult conversion. Carrier billing enables the push from trying apps to buying apps that much more easily.

Nokia Indonesia head of technical sales Gustaff Martin revealed a number of facts to DailySocial with regards to purchases made using carrier billing. We know that XL subscribers are limited to spending Rp 103,540 per app and Rp 200,000 per month total. What we don’t know however, is why. According to Martin, the individual app limit is set at that particular figure to roughly equal to USD 10 with a pegged exchange rate. The monthly limit is capped at Rp 200,000 to reduce over spending by consumers and to limit the risk from any possible fraud.

Martin said that should this carrier billing scheme become very popular, XL may consider raising this limit in the future. Asked whether this will extend to other operators, he said that it’s a possibility but he wasn’t prepared to discuss any further, emphasizing that XL is the first to implement this payment scheme in Asia Pacific for Windows Phone.

In terms of revenue split, according to Martin, the carrier partner receives 15% of each app purchase with the rest being split between Microsoft as the operator of the Windows Phone Store and the developer and that this is uniformly applied to other carriers partners who enable carrier billing for Windows Phone store purchases.

Microsoft Indonesia’s director for development and platform group Risman Adnan believes that this partnership will encourage more Indonesian mobile app developers to create more and better quality Windows Phone apps, knowing that app purchasing has been made easier which will allow them to earn more revenue from app and in-app purchases.

It wasn’t disclosed whether other Windows Phone makers will have access to carrier billing in the future although in Microsoft’s best interest, as well as the interest of the entire Window Phone ecosystem, this exclusivity deal between XL and Nokia must have an expiry date.