FlightRadar24 utilitises the same idea as Skymap but instead applies it to planes in the sky - simply launch the app, point it at a plane overhead and you can see where it's come from and going to, which carrier it belongs to, current speed, altitude and other interesting information. Exactly how useful it is is debatable, but I think it's kinda cool and an excellent tech demo if nothing else! You can also use a regular map view to view flights.
Head on over to the Play Store (or your chosen place for android apps) to download the app, a limited free version is also available.
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