Yes! You'll have offline access to your personalized guidebook in the ViaHero app (download for iOS or Android), plus offline access to your custom maps via the Google Maps app (iOS/Android). 

Guidebook: Once your Hero completes your guidebook, it will automatically save in the ViaHero app on your mobile device. If your Hero makes updates, swipe down from the top of the screen to refresh and load updates.  

Customized Map: Your customized Google Map link is located in the Maps section of your guidebook. Please review these step-by-step instructions to download offline maps and load your customized map overlay before you depart on your trip. With everything saved on your mobile device prior to departure, you'll be able to navigate to all of your Hero’s recommendations, which are highlighted on the map, plus any place that exists in Google Maps—all offline! 

While traveling, remember to turn OFF your data to avoid roaming charges, but make sure the GPS on your mobile device is turned ON to be able to use the locator function within the Google Maps app. Since your guidebook and maps are all pre-loaded, you won't need any wifi or cell data connection to navigate.

Remember: Download the offline Google map and load your Hero's customized map overlay before you depart on your trip to ensure that all locations are saved in the Google Maps app.