Microsoft first unveiled its low-cost 256MB of RAM Windows Phone devices at Mobile World Congress earlier this year. Although Microsoft warned parts of Windows Phone would be restricted on handsets with 256MB of RAM, the company said it expected 95 percent of apps would still install and run just fine. Nokia's Lumia 610 has started to ship in Europe and a Windows Phone fan site in Spain has discovered that a number of popular apps refuse to install on the handset.

Skype, Tango, Angry Birds, and PES 2012 all refuse to install at the moment, presenting a RAM warning in the Windows Phone Marketplace. It's too early to say whether the app developers involved will be pushing out updates to support 256MB of RAM devices, but the restrictions on such popular apps appear to signal the first type of hardware fragmentation on Windows Phone. Microsoft may claim that only five percent of apps will have difficulties on 256MB of RAM devices, but if these are popular ones, including Angry Birds and Skype, then the company could find it difficult to market the advantages of such low-cost phones.