If one uses current high technology of batteries and hardware, the smallest terminal for the geoearth orbit satellite is of the size of A4 page and is of the weight of about 2.5 Kg, which is certainly not possible to use it for usual mobile communication purposes, but this one a INMARSAT-M, a standard gives you connectivity, but then one must look at into: "Are there no other ways by means of which we could use a satellite for connectivity? Yes, non-geo-stationary earth orbits satellites in lower orbits are required".