It wouldn’t be an understatement to say that much of Microsoft’s future relies on Windows 10 for mobile being successful and there’s no way for that to happen if the operating system isn’t accessible. Many people were worried that they would need to purchase an entirely new phone to get the new operating system when it’s released but Microsoft has announced that Windows 10 will be available as an upgrade to anyone who owns a smartphone that’s already running Windows Phone 8.1.