I run Memory Maps on my Nexus 7 gen 2. In my experience it is one of the more powerful apps with customizable data displays, easy to create waypoints and routes, and the charts look like your NOAA paper charts as opposed to the proprietary charts you will see on navionics. It can also work with maps other than charts so if you are in an uncharted area like far upstream or a small inland body of water it provides some background. The biggest downside to this app is being limited to landscape view, it does not work in portrait orientation and the screen of a nexus 7 is polarized such that it cannot be read through polarized glasses in landscape view. I have yet to find a waterproof case for it other than the generic sleeve type. Occasionally it will have latency and I have to restart the app to get the position to update, I believe this is a hardware issue. I use the internal gps receiver.
