Google+ launched its apps for iOS and Android last year, and have said that an app for BlackBerry OS and Windows Phone is in the works as well.
Now, the official Google PR rep for Google Germany, Stefan Keuchel tweeted that Google+ is working on a Google+ app for Windows Phone. Google+ still hasn’t found success, but Google is pushing it with all its might. Google only has one app for Windows Phone, which is their search app.
