Create application build on xcode 5 through storyboard .
First view : one text field for mobile number then submit button . It will send activation code to the same number (sms) the user will take this code and enter it in order to go the next view otherwise will not be accepted .
Second view if the user entered right code : live chat view will open he can communicate with the company in private way .and one button for sending his location . Of course the user will use his iphone to chat but the company can user web browser or iphone , ipad . The choice is yours .