Direct carrier biller Fortumo will support Windows 8 apps, making it the first mobile payment company to do so. The company already provides in-app payment support for the Android and web apps of more than 70,000 online merchants in more than 150 countries.

"With the launch of Windows 8, developers now have an additional platform on which to build and distribute their applications," said Rain Rannu, co-founder of Fortumo. "We will be helping them to develop new revenue streams from the get-go."

Rannu said Fortumo's mobile operator billing in 80 countries will provide a seamless payment experience for Windows users without their having to register or own a credit card.

Fortumo's system lets customers pay for digital goods by placing the charge on their mobile operator bill. The company has payment connectivity to more than 250 mobile operators worldwide, reaching four billion mobile users. The system supports 32 languages and more than 45 different currencies.

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