Ever since Garmin messed up Active Captain's on-line chart viewer's functionality, I have been looking for something similar. Thanks to cruisingChick's post above, I think I have found it.
The Navionics Chartviewer uses vector charts unlike AC's raster. That is a plus and a minus, but I must say Navionics chart rendering is as good as I have seen. Buoys are clearly green and red (unlike others) and depth contours and values are comprehensive (unlike others).
I particularly like it's route preparation and saving capability. It lets you easily link waypoints to create a route. There is a box to the left of the screen that gives the length of each segment, the time to reach the next waypoint based on the boat speed you enter, and even the fuel burned for each segment as well as overall totals for these.
Presumably these cloud saved routes can be synced to a tablet app or downloaded to a Navionics chartplotter.
The Navionics chartviewer does not give you Active Captain icons or data, nor does it give the ability to switch to road or satellite views. If Garmin and Navionics could team up to integrate their two chart viewers that would be the best of both worlds. How about it guys?
David