High altitude platforms (HAPs) and satellites have been promising to revolutionise mobile connectivity for at least 30 years. HAPs such as drones, aerostats and balloons have been suggested for spot coverage, emergency use and more recently projects such as Google Loon tried balloons to deliver connectivity in Africa. Starting with Iridium, satellite operators have tried to connect to handsets since the late 1990s. Yet I doubt that many cell phone users have ever made a call, or connected, via anything other than a terrestrial base station.
