I bought htis about 3 weeks ago beause we sometimes do not want to cary our smartphonee.  In those times that we don't we have to find the hidden key and unlock the door.  That has all changed since we purchased the Smart Keypad.  You can setup multiple codes for each person in your house and more....you even get a failsafe code as well.  Very easy install and only took 10 minutes including opening the box.