Type in all the Codes of your family and friends in this application and keep them all stored in one place. You won’t have to wonder what code to use to get into Alison’s place for example!
Centralise all this information in your iPhone, and you’ll know where to look for your codes.
You won't have to wait in front of your friends' doors and call them to ask for the code.
TV Shows 
Quiz Animal : Calls of the wild!