Called "Mobile Compatibility", a new report notes the usability issues that Google does not like.

A new informative report has just made its appearance in Google Webmaster Tools. Accessible bottom of the menu "Search Traffic" and called "Mobile Compatibility", it is thought to solve usability issues and mobile SEO of a website. Among the errors it may fall and list "tactile elements too close", "use of Flash content," "small font", "size is not suitable content to display" or "window non display configured. "
Click on errors allows you to see which pages Google Site met them, and when they were last detected. A link also refers to an official help page that can help resolve problems.
This new feature comes as Google has deployed in new countries, including Germany, the penalty in the referencing mobile sites using Flash content. Deployment in France should no longer delay.