User Manual Garmin 010-02246-02 STRIKER Cast GPS

Definitely works on the move. I drag it behind my boat using an electric motor but there is a limit on how fast I can go before losing the signal. Choppy water makes it more difficult to use while moving. It holds it charge reasonably well although I always go out fully charged. Over all I have been very pleased with it performance.

Yes, it never connects to cell service. It Bluetooths to your phone. I used it 70miles away from the nearest cell coverage without issue. You can still record your tracks and view your depth chart just the same. You can download maps to your phone while u have cell service though

Yes, as it doesn't use cell signal. It works as long as you are in the Bluetooth range of your phone.