That was the message sent via “text mob” that guided protesters forward at the Republican National Convention street march in 2004, relieving them of the panic that no doubt would have ensued when the plumes of smoke rising up ahead were observed. Text mobs also helped shut down San Francisco for 12 hours when the war in Iraq broke out in 2003 and the initiation of the Orange Revolution in the Ukraine was signaled by the sound of student cell phones ringing.