A Houston, Texas area young woman was walking her dog when the stuff nightmares are made of occurred. A man grabbed her from behind and put his hand over her mouth promising to "help her." He wasn't helping her, he was attacking her. That's when, she scared him off by calling iPhone with an iPhone trick. If you press the volume button and lock button at the same time for two seconds, if will give you an SOS option. If you slide over, it will automatically call 911 for you. This trick was enough to scare the attacker away.
To make sure your iPhone will do this during an emergency, check your emergency setting on your phone.