My boat has all the electronics on the flybridge but guests are always asking where are we? How much longer? What's our ETA? etc. So, we had an old iPad that was in a desk drawer for two years, mounted in the salon. Now, compliments of Blue Tooth, people can see in the salon, exactly what I'm seeing on the fly bridge!
The photo below shows that I was checking on the battery bank status while underway. (Batt 1 is the house bank and batt 2 the engines & generator bank.) Anything that I'm viewing on the master plotter can be shown down below.
All the money for the electronics was spent on the fly bridge....having the same info in the salon came from an old iPad (obsolete) & Blue tooth down below.( i.e.: Fuel, SOC, navigation, etc,)