The app age rating system developed by the Entertainment Software Ratings Board (ESRB) and CTIA, the US wireless association, is set to go live without the participation of Apple or Google.

The new system for rating mobile apps based on the “age-appropriateness of their content and context” was first reported last week. The ESRB has been running a similar ratings system for computer and video games for a decade.

However, Apple and Google appear to be happy to continue with their own controls. Engadget notes that this could be related to the fact that the ESRB rating system relies on developers filling out a questionnaire about the content of the app rather than the review approach used by Android Market and Apple’s App Store. The ESRB will regularly test applications to check they match their rating and will “closely monitor consumer complaints”.

According to the CTIA, AT&T, Microsoft, Sprint, T-Mobile USA, US Cellular and Verizon Wireless will adopt the system, and other app storefronts have indicated their interest in taking part.

CNet News reported that CTIA developed the rating system to call for "voluntary self-certification of apps," that will “provide consumers with the information and tools they need to make informed choices when accessing apps using a wireless handset.”

Apple’s App Store currently has comprehensive age guidance. However, Android Market currently has just three maturity levels – low, medium and high – and Windows Phone has little age guidance beyond a ‘family’ category.