Summary:

One more technical, and PR, setback for Microsoft (NSDQ: MSFT) and its fledgling Windows Phone 7 operating system: the company yesterday con…

Windows Phone 7

One more technical, and PR, setback for Microsoft (NSDQ: MSFT) and its fledgling Windows Phone 7 operating system: the company yesterday confirmed a persistent rumor that some WP7 phones are sending up to 50MB of data over 3G networks on a daily basis, even when the handsets are idle.

In a note posted by SeattlePI, Microsoft has put the blame on an app — although it is not specifying which one — and says that it is now working with the publisher to fix the issue; it is also investigating whether there could be additional causes for the “phantom” data send.

Microsoft says a “low single digit” percentage of users have complained about the problem so far — although it may be the case that other users have not noticed. It did not say whether it would be informing other users of the offending app of the possible data glitch.

Considering that 50MB/day over a month works out to 1.5GB, the issue could prove expensive in some cases where operators charge hefty fees for exceeding monthly data limits that are normally the 100s of megabytes.

Windows Phone 7 seems to be still very much in its teething phase.

As of the end of December, 2010, there were 5,000 apps in Windows Phone 7′s Marketplace digital storefront. Not a big number when you compare it to the 300,000 apps in Apple’s store, or 160,000+ apps in the Android Market, but potentially a more attractive environment for developers tired of trying to swim to the top in a sea of other products.

Meanwhile, Microsoft has been trying to build up more momentum around the store, both for users and developers. Earlier this week, Microsoft began to roll out operator billing services for its apps — meaning that instead of charging to a credit card, users can pay for apps via their operators’ bills. The thinking is that this will make it easier to make app purchases — by some estimates, between eight and 13 times more likely that a user will pay for a service because of the ease of use.

The service, which is being run by the mobile billing company Mach, has launched first in Australia with Telstra. Charles Damen, Mach’s VP for mobile content and applications, tells us the billing service will be rolled out in further markets “according to Microsoft’s schedule.”

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