Almost good enough

The photographed map images are obviously not as good as those generated directly from NOAA data, but are quite readable and will be pleasantly familiar to those who have worked with traditional charts.
Waypoint management is simple and intuitive, but its a shame that you cannot stack a set of waypoints as a single route. This is especially unfortunate since the waypoints use dead simple route planning, and no effort is made to keep your vessel afloat,
The Track display is disappointing, since it ignores position-at-time, opting instead to display total distance travelled against instantaneous speed.

Even with these complaints, I find this to be my favorite (current) marine navigation app in its price range.

Tar2 about iSailGPS : NOAA USA RNC Charts