If you want to change the navigation voice, please go to Menu → Settings → Regional → Voice
You can choose between Standard (in Manage voices section) and TTS voices. Standard voices provide all instructions needed for navigation in higher sound quality in comparison with TTS voices. On the other hand TTS voices are able to read texts, therefore they are pronouncing also street names and road numbers. TTS voices allow users to modify custom warnings as well, either for approaching speed cameras, exceeded speed limits or any other events in Menu → Settings → Sound and notification → Notifications
Language of the application can be changed via Menu → Settings → Regional → Language
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