Another innovation was a smartphone app called Walking Edge, developed by a Republican technology firm. It allows canvassers to access canvassing maps and addresses on their iPhone, BlackBerry or any smartphone with GPS. Volunteers can see in real time who has been contacted and who hasn't, who is undecided and who is committed. On election day, the Walking Edge data was constantly updated so Brown's supporters could see who had voted and who hadn't, and then go to their houses and prod them out to the polls.