The free what3words app allows you to find, share and save precise locations using what3words addresses. You can also navigate to what3words addresses using compatible navigation apps such as Google Maps, Waze and Navmii, or ride-hailing apps like Uber. The app can be used offline, and is available for iOS or Android devices.
You can find handy step-by-step instructions on how to use the what3words app here: http://what3words.com/how-to-use-the-what3words-app