Worried that your kids are playing games that perhaps they shouldn't on their mobiles? Microsoft is too, it seems, as it has introduced PEGI age ratings to its Windows Phone platform.

The PEGI system is the standard form of classification for video games in the UK, announced by the  government back in 2009 as part of its Digital Britain report.

PEGI Express is a mobile based system, with developers able to get their games rated with a tool built into the Windows Phone platform.

"At Microsoft, providing parents with the tools to help keep their children safe online is a top priority, and we have made considerable investments in this area both in our Windows environment as well as on the Xbox 360," said Chris Lewis, VP IEB, Microsoft EMEA.

"Given the fast growing popularity of mobile gaming amongst a younger age group, we felt that it was critical to apply those same rigorous standards to our Windows Phone devices as currently apply to Xbox and Games for Windows titles."

It makes sense. With gaming on mobile devices becoming so prolific and ever more realistic, it seems only fair that parents with concerns have the same guides in place for their kids' phones as they do for their consoles.