This is Not from Mozilla. Mozilla only supports Firefox for Windows, Mac OSX, Linux and mobile Firefox for Android 2.3+ and the Firefox OS for some phones. They do not charge for the Firefox browser on anything they support from mozilla.org '''None''' of these so called Firefox apps examples at links below is from mozilla.org as look who each is published by. They are breaking trademarks as per https://www.mozilla.org/en-US/legal/fraud-report/ *http://apps.microsoft.com/windows/en-us/app/53602a32-ec98-4011-90ef-39fa60a83ae0 *http://apps.microsoft.com/windows/en-us/app/fcb9492f-46cb-42dd-88a9-1a662976762d *http://apps.microsoft.com/windows/en-us/app/12803839-2b13-4054-96fa-8b40fef1d751 There are several claims of Firefox at store http://windows.microsoft.com/en-us/windows/search#p=1&q=firefox&s=Store and if Mozilla had a legitimate one there, there would only be one and it would be free in price and free of any junk.