Tiangong 1 is a Chinese space station under construction that is in orbit since September 29, 2011.
This application places Tiangong 1 on the map in real time, and other 146 satellites, including the ISS. (I recommend install before "ISS?" , is more easy).
Calculate the orbit from the current time of device and TLE data, which obtained www.celestrak.com.
Red line is drawn 50 minutes before and after the current position of the satellite.
The user's position is marked with an android with the arm held high, surrounded by a semi-transparent red circle.
The red circle shows approximately the area in which the satellite would be visible by the user.
Internet access is used to obtain maps and update once a day TLE data. More zoom means more data traffic.
From the main application window, pressing the menu key, you can select other satellites.
At night you can see many satellites, some are very bright as the ISS and others require a more darker sky.
From the main application window, pressing the menu key, you can select "Visible Pass".
From this screen we have the date, time, position of the observer and two buttons.
Pressing the left button (arrow circular with dot in the center) are calculated the visible passes for all satellites for tonight, sorted by time of onset.
Pressing the right button (circular arrow) the visible passes are calculated for the next two days for satellite selected on the main screen.
Clicking on one of the visible passes entered the 3D locator.
The locator uses accelerometer, the compass of the device and the calculated data to show the position of the satellite on sky from observer's position.
That is, when we moves the device to the sky shows a red triangle in the position of the satellite and a red dotted line showing the visible pass.