SEAiq USA is a full-featured marine navigation app for the United States. It automatically downloads and displays charts from NOAA and the US Army Corps of Engineers for the regions you select.
Features include:
* Waypoints
* Routes
* Tracks
* Night color modes
* Anchor alarm
* Automatic download and display of weather (wind & isobar)
* Chart measuring tools (EBL/VRM)
* Wi-Fi-based NMEA and AIS
* Vector charts
No purchase is required to view charts. Premium navigation features are enabled during a 7-day evaluation period. After that, an annual subscription is required. Existing one-time purchases retain the features they unlocked.
Continued use of GPS running in the background can dramatically decrease battery life.
Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/