Tango, the popular cross-platform video calling application for PC, Android and iPhone, launched on Wednesday as the first video-chat application for Windows Phone 7.5 devices. You will need a front-facing camera to take advantage of the face-to-face chat feature, which means you’ll also need to own one of the newer Windows Phone 7.5 devices such as the Samsung Focus S, Samsung Focus Flash or HTC Titan. We installed the application this morning and gave it a quick test over a 3G network. The video quality was poor, but we were alerted that this was because of a weak 3G signal. Still, we loved the user interface on Windows Phone 7.5 and found it much cleaner than the Tango application for Android. In addition, it automatically filters out your address book to show only contacts that have Tango installed, which was a nice touch. The application is free and is available in the Windows Phone Marketplace now. A video of the application follows after the break.