Basically your password switches literally every minute unbeknownst to anyone (girlfriend/boyfriend, mom/dad, annoying brother/sister, etc) hovering over your phone trying to figure it out.
Your password will be whatever the current time is. For example the time is now 5:34pm so your password will be "0534". When the time turns to 5:35pm your password will now be "0535". Quite simple yet secure and cool!
sent from my neXus 5