Google Maps now allows you to download maps and navigate offline, although the service is currently only available for Android devices.
To use offline navigation, you must first download the section of the map you need for it trip your. You'll be able to do this beforehand when you're in a Wi-Fi area, but you won't have turn-by-turn directions. You mean of course that you can't get vehicle traffic information (where supported).
You can, however, access information about positions car park, όπως τις ώρες λειτουργίας, data communication, ratings, etc.
Once you have downloaded a section of the map, the Google Maps will automatically turn on offline when you lose your connection.
Google did not report when exactly the service will be available for iOS users.