Hi, thanks for taking time to ask this question.
There are many apps for offline navigation but most are paid apps.
You can use:
Sygic, TomTom, Navigon and such. Please take a look in AppStore in the navigation category for more apps. All those apps I mentioned are paid apps.
There is also Maps, Google Maps and Waze among others. Some of them offer offline navigation as well but my belief is those aren't as good as the paid apps.
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