Heck, we have two point-and-shoot CAMERAS on board with GPS's! Two GPS handhelds - one with a world map, three computers with GPS pucks, two VHF radios with built-in GPS and nav software, and even a chartplotter for when we feel old-fashion.

And we have somehow inadvertently collected these over the years without consciously trying to. The matter is that you get GPS in almost all consumer products nowadays. The cameras are an example, so is the VHF handheld. Not to mention the GPS pucks were thrown in for free from old mapping software packages (before map apps were born). I am sure we have something else on board with a built-in GPS that we are unaware of.

Most of these can be run on dry cells. The others charged with a cigarette plug or tiny inverter. We have 4 independent battery banks on board, so if everything hits the fan with the house bank we have options.

In fact, we took a direct lightning strike that took out all fixed electronics, most of the electrics including our main inverter, and shorted and boiled the house bank. We kept cruising for a month with no problem - still had 4 usable GPS's and 3 non-house batteries and handheld inverters to operate them on board. I laugh when the lightning strike argument for paper charts comes up and just show them the camera in my pocket.

And we are Luddites - we haven't even succumbed to the tablet/phone thing yet! Paper charts are just plain medieval today (although I like to keep a single large-scale one for our cruising grounds - in this case the entire Caribbean Sea - just because I like to look at it).

Mark