The image attachment button is not working for me but here is the link to photo of arrangement :
https://drive.google.com...LtNfkXd/view?usp=sharing ]tablet arm[/
A tablet is a widely used alternative to a plotter ,running a cheap but capable navigation app plus charts updated yearly.
In my case a 10'' Android Samsung (about £200) running 'Marine Navigator' (£10) plus charts from 'Visit My Harbour'.(UK only £17).
I also double up with the 'Open CPN app' plus charts from 'O Charts' (similar costs) because some particular features in that app are really useful .
I don't know how people making major voyages can cope with the small screen on a smartphone as I find the ability to see more than just the immediate environs and the detail of soundings essential .Since the mainsheet on our Parker Seal is now taken to a track on the bridge deck we make use of the old mainsheet horse to mount our tablet on a cheap chinese adjustable swing arm ,so well protected up under the sprayhood,away from rain and seas that make it over the coachroof and some sunlight.We find this works well.
Some pay a great deal more for a rugged waterproof tablet with greater brightness .You can pay as little as £100 for a capable tablet and one with reduced battery life can still be used ( connected to USB) ) for this not so demanding purpose.
Obviously the tablet has other useful functions and there are various ways to display AIS in either of the apps mentioned..
Speed over ground will be shown continuously on screen in either app .A wind system can be useful ( e.g. NASA clipper) although if you've come from smaller boats your experience there might well carry you until mast work is convenient.