Cruisers Net have a neat,seamless NOAA chart which can be updated/edited by the users,presently only for the Southern US and
Florida. You just do a right mouse-click on the location of interest which creates an access URL you can send with your update/edit request to Cruisers Net.
I have made inquiries to find out if editing/updating can also be made available for other popular yachting areas around the world.
Apart from the seamless NOAA
charts of the US and
Bahamas,there is also the usual
Google options.
Really a bit like OpenSeaMap which also allows user editing/updating,but, alas presently without soundings.
Tore