I am vacationing in the Alps, and trying to add hiking trails to the OSM database. In deep alpine valleys (definitely not canyons) I often lose the satellite signal, and looking at the satellite display see that most are low on the horizon, blocked by the walls of the valley. If there were twice as many satellites available there would be no problem!
There seem to already be high end products that use both GPS and GLONASS satellites; does anyone have any information as to how soon we may expect consumer versions?