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No. A wifi connection is best, but you don't even need that. You can add an SD card and store maps to it using an app called MapFactor GPS. You can download turn by turn voice guidance too on that program. You could also download NAVfree USA. Same type of internet-free GPS. Finally, there's always Google maps. Just save maps of where you want to go (you can save up to six maps offline). The key is to first start navigation while you have internet. Then you can leave and still navigate without internet
No