While iNavX is a great tool, I switched to Garmin Bluecharts for our charters. Here are the main reasons why. Some of the reasons may be a couple of years old now, but I�ve been happy and haven�t looked back.
1. Charts are MUCH less expensive on Garmin.
2. Charts are MUCH easier to purchase and download through the App Store versus setting up X-Traverse Maps, downloading the charts, etc.
3. I like the Active Captain integration for Garmin (though you don�t need it as much in the BVI�s with this great TTOL board on your side).
4. I liked being able to plan out my routes and waypoints on my iPad and then easily email them over to my phone. So that way I knew I had a couple of backups to my primary device, which was my iPad with a Nuud waterproof case and RAM mount.
Yes, it all works offline so long as you have a 3G/4G device with the GPS chip in it.
Here is another thread on this topic.
TTOL Navionics versus Bluecharts thread In that thread, I posted this Garmin promo video if it helps.
Bluecharts mobile promo video
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