OpenSky Network is described as 'The OpenSky Network is a non-profit ADS-B exchange for sharing real time aircraft data broadcast over the airwaves. The network consists of thousands of sensors connected to the Internet by volunteers which collect ADS-B and Mode S broadcast data' and is a Flight Tracker in the travel & location category. There are more than 10 alternatives to OpenSky Network for a variety of platforms, including Web-based, Android, iPhone, iPad and Android Tablet apps. The best OpenSky Network alternative is Flightradar24, which is free. Other great apps like OpenSky Network are FlightBar, ADS-B Exchange, RadarBox and FlightAware.