Thread: Marine e-charts.

New to this stuff so I could do with some advice on the best way to get good charts on my plotter.
I have a Garmin Echomap 62+ with the shit base map on it and am after something with good contour and the ability to track and mark waypoints.
I have found a couple of really good maps (one on the internet and one is an app) but both need cell coverage to work and ideally I don't want to be pissing around with my phone when I have a chart plotter screen right in front of me.
Any suggestions would be appreciated.