Wireless operators expose their application programming interfaces (APIs) to developers to make services richer, more tightly integrated and robust, but they really do it for another important reason: to make money off their assets.

To date, the monetization part has been tricky despite huge growth projections thanks in large part to transaction-based billing systems that weren't built for an app world. API company Apigee is hoping to help with a new platform it says will let operators monetize their APIs without ripping out their legacy billing systems.

The Monetization Services platform, an add-on to Apigee Enterprise, tackles billing from the actual creation of rate plans and management of limits and notifications associated with them to creating the bill and pushing it directly to the developer portal, as well as changing the bills on the fly if needed. The company says it gives operators the flexibility to bill however they see fit – with a flat fee, by volume, via a bundle, through freemium offers or even through a set or variable revenue-sharing arrangement with developers.

Apigee acquired the failed Wholesale Application Community's technology assets just over a year ago, including its multi-currency billing platform, which has been adopted by a range of wireless operators including Telefónica, Telenor, AT&T, Deutsche Telekom AG, KT Corp., LG Telecom, SK Telecom and Smart Communications Inc. Anita Paul, Apigee's director of API products, says direct carrier billing is a separate service, but comes into play on the Monetization Services platform if developers want to deduct their revenue share directly from the carrier bill. (See Telefonica: In APIs We Trust.)

Operators desire to monetize APIs has caused a lot of them to look outside of the long-tail consumer market they started in to the enterprise. Most have also started looking at using APIs in their own networks for things like software defined networking and IMS rather than to help developers build apps. (See CTIA: Carriers' Developer Love Fest is Kaput and Operators Cut AlcaLu Out of API Equation.)These are trends that Paul says Apigee has seen, too, in its work with all the major wireless operators. She says that operators have become more interested in the enterprise because of how hard it is to build a business in consumer apps where 80 percent of the income comes from 20 percent of users.

"It's easier revenues in the enterprises, less overhead," she says.

Apigee is making the monetization platform available next month either in the cloud or on premises and says it integrates with operators' existing backend Service Provider Information Technology (SPIT) processes.

— Sarah Reedy, Senior Editor, Light Reading