[GPSNavX]

Course Up will be supported in iNavX (targeting version 3.02). I have not received much demand for it probably because most realize with raster charts that besides for the geography all the chart text (i.e. soundings) rotates making it more difficult to read. Furthermore the iPhones GPS and/or compass just isn't that spot on. Specifically SOG and COG are not that accurate at lower speeds (under 5 knots) on iPhone. iPad is much better on the GPS side, but its compass is still very error prone. At times, I can see 30 degrees of difference between iPhone and iPad compass. iPad compass appears to be very sensitive to the angle held. So course up comes with some caveats of less than perfect accuracy.

I added Course Up to MacENC years ago and I don't think I have received one email in regards to it either pro or con.

I have Navionics app for iPad and it does not appear to support course up like their app for iPhone.