Tango's official website does not provide a download to a PC version as of 2015, but Tango can be downloaded onto any Windows computer from Softonic. The PC version of Tango allows you to call any user on a mobile version of the app.
The PC installation file for Tango is available from tango.softonic.com. From the main page, click on "Free Download" to start the download. Once the file is on your computer, launch it and press "Install." From the installed Windows version of Tango, you can video call and voice chat with any user on Tango for iOs, Android, Blackberry or Kindle.