Now you do not have to waste any of your
mobile data for using maps app. An awesome app is available in the AppStore
which allows you to use GPS offline.
“Maps.me”, an app which allows you to
navigate directions without having to use internet connection.  All you need to do is download the map of your
country (this is a onetime process) and you’re good to go.  
This map covers all the countries (345
countries and island) including small countries like Nepal, Mongolia, Bhutan
etc. The map not only shows you the place but also shows you the direction,
distance, and also a voice navigation.

This is a completely free app that you
need to download immediately. Download it from here