Car Rental GPS vs Google Maps

I recommend that you check out some things before you decide.

To use your cell phone in France will likely require the purchase of service specific to France. How much will that cost and how convenient is it?
Do you own a GPS that will accept an accessory chip with maps of France or can accept a download of maps of France?
Michelin maps are very good and very detailed, as an alternative. This may be the lowest cost option.
Note that some places that you might stay at may not have a street address, but GPS coordinates.
On my May trip to France, I used my own GPS and purchased the accessory chip. It worked well.

Have fun,
Ed

I've used Google Maps in France and it works great. The best feature is that it even works offline if you download your maps in advance. I don't know how they do it, but it still gives voice directions and will recalculate your route if you take a wrong turn. So you avoid data roaming. See this page for how to do it. I'd be sure to bring a car phone charger and a phone mount--plus paper maps just in case.

CoPilot seems to do similar - navigate whether you have phone service or not. I'm still playing with it and won't recommend it until I've road tested it in France next month.

Your T-Mobile coverage should be good in France, where you'll be connected to the Orange network. Last year, I used a combination of Google Maps and a printed Michelin map. At a more than one intersection around the Luberon region of Provence, I did have service and found accurate road directions through Google.

My husband and I purchase REAL maps from Barnes and Noble. We have used the Borch brand maps. They are laminated and have good detail. We have France, Italy and Germany. We have not looked for other countries because we haven't needed them yet.

Some people may complain about their regular large size map size but I can deal with that by folding it.

Neither of us want to have to use Google maps or a GPS system. On fact, the last time we rented a car in France, he was asked about renting a GPS system. His response was that he had a GPS system and her name was Bev.

Call us old fashioned or technologically challenged. Laminated paper works for us!

We used the Garmin Western EU app with downloadable maps on our iPhone 6. We had no iPhone cell service and it still worked great. Drove to the Loire Valley from Paris, back to Paris, and used it as a map in Paris. Either it doesn't have a bike (or Walk) setting, or we couldn't figure it out, but that would have been nice, too because we road Velib bikes in Paris.

For driving, though, it was lovely. Even told us where the nearest grocery store, gas station, ATM, etc. was.