GPS users--how much data do you use in a trip?

I remember using my old 3GS as GPS replacement without a sim card.
You should be ok

 

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Tom Tom and Navigon have the map data on the device. MOTION X Drive doesn't and constantly downloads data. So, it totally depends.

Plus there is data like traffic/weather to worry about.

 

You are right!
Make sure you use an app that has the maps already.

 

Just got back from a 6 day vacation. I used the MapQuest app exclusively for navigation. I was really surprised how well it worked even when I only had edge data. We did a lot of driving (the rental car bill said 926 miles). MapQuest was up and running during most of this.

I've pretty much decided to keep unlimited data but was curious how much data MapQuest used. Obviously it's nearly impossible to separate out MapQuest data from other data (web browsing, email etc.) but the grand total from those 6 days was 138 MB.

 

Navigon and TomTom dont use data

im using those GPS apps on my old 3GS with no sim card in it