Not currently since it's single hop bounces from ground to sat to ground. Eventually though they want to mesh the satellites with a laser network which will allow peering between satellites. Once that is done they will be able to cover the entire globe.

It depends on how far you are. With the current system at least 1 Satellite needs to be close enough to a ground station. So that means from your boat up to the sky, and from there to land.

It has also been suggested that at strategic locations you could have swimming ground stations in order to cover a pretty large area.

Eventually however it will cover everything as the satellites will communicate directly between each other with lasers.

Where "close enough" means that you would need to be within about one-and-a-half-thousand kilometres of a ground station (using words not numbers because it's a bit hand-wavy).