SEAiq

This is the only marine navigation app that allows you to load your own charts in a variety of standard formats, including: S-57, S-63, iENC, and BSB/KAP. It also includes the ability to automatically download charts from NOAA for the USA and free download of raster charts based on satellite imagery.

Other features include:
* Waypoints
* Routes
* Tracks
* Night color modes
* Anchor alarm
* Automatic download and display of weather (wind & isobar)
* Active Captain Interactive Cruising Guidebook
* Chart measuring tools (EBL/VRM)
* WiFi-based NMEA and AIS