Google+ "locations" didn't cut it. It updates way too infrequently. In PLAY, I came across Guibber. It is even far superior to Latitude. You can track your friend/family member in real time, with speed and altitude. Just be sure to choose wise settings, so as to not tax your battery too much. The newest version is great (the original one had some serious limitations). You do have to have it installed on each phone, and with appropriate "permissions" given (like Latitude).