I've looked at various iOS charting apps to find one that leveraged the information available on my boat network - speed, heading, COG, depth, etc. I never found anything that really met my needs.
I went back and found an app I had liked and rejected a year or so ago: SEAiq Pilot. There was a lot to like about the app but I'd be danged if I was going to spend $400 on an iOS app.
However... I discovered I was confused by how they sell their apps. There are really 3 different versions available:
* SEAiq Pilot is intended for use by professional pilots on big ships. It has a lot of features focused on that market such as showing separate course vectors for the bow and stern, showing the swept path of the vessel, showing a trial Rate of Turn, and tons of stuff I don't understand. $400
* SEAiq USA is the 'recreational' version of the program. It has 80%-90% of the functionality of Pilot. It can download and display NOAA and Army Corp of Engineer charts (vector and raster). $25
* SEAiq Open is the same as SEAiq USA but adds the ability to install S-63 as well as charts from PRIMAR and ChartWorld. $50
As a recreational boater my take on this is: $25 if you need the US Govt charts; $50 if you want to buy and load international charts.
So what did I get for my $25? The things that are important to me:
* Integrated, free downloads of NOAA charts
* Management and quilting of both vector and raster charts
* Decent WP and route creation (and no auto-route)
* Very nice route export/import/backup via GPX files
* Export of WPs to my MFDs via WPL sentences
* Very nice import/export/backup of the app configuration via files
* Excellent NMEA 0183 handling including diagnostic displays of sentences received, data, and errors
* Excellent handling and display of AIS data. AIS data is much more useful to me in this app than on my MFDs.
Nice to haves include:
* Tide and current options (several options, free and paid)
* Download and display of GRIB data
* Active Captain integration
* Various alarms
* A very cool anchor monitor
Also include with the app is the most detailed documentation I've seen in a product of this kind. The doc is available from within the app even when the app isn't connected to the internet. Maybe this is old-school but I view it s a huge positive.
I've dealt with their support on a few questions and received some of the best answers--quick, complete and informative.
I'll also note the apps are updated in the app store every few weeks. Again this appears to me to be a 'professional grade' offering with serious ongoing development.