Welcome to the home page of the Amateur (Ham) Satellite Predictor AmsatDroid.

About HamSatDroid

This software predicts future passes for amateur radio satellites for a specified location and period of time. It runs on the Android operating system (v 1.5 and above).


  • Calculate passes for up to the next 24 hours
  • Graphical pass display
  • Map view showing current satellite position
  • Update keps from a file on SD card or directly from AMSAT's webpage using your phone's internet connection
  • Set home coordinates from Network or GPS

Satellite Position Calculation Algorithm

We have moved to using a Java implementation of the NORAD SGP4 Simplified Perturbation Model as implemented by Dave Johnson, G4DPZ rather than the "Satellite Education News Tracker".  This is an open source project known as predict4java which is in use by the GENSO project, amongst others.

Pass Calculation

The SGP4 based pass calculation  give more accuracy in terms of AOS, LOS, TCA and position. Please read the NEWS for more information.