GEO satellites orbit at a distance of 35,786 km above the Earth's equator. India's first GEO communication satellite was the APPLE which stands for Ariane Passenger Paylon Experiment. It was put into orbit during the third test flight of the Ariane launch vehicle.
APPLE weighed 350 kg, and for more than two years, it successfully served as a communications satellite for India. APPLE was used several fields communications including for the relay of TV programmes, and radio networking.
APPLE proved to be an important learning experience for Indian space scientists in the operating geostationary communication satellites.