Sail Buddy is a light-weight app that displays course, speed and NMEA data in a fast, clean interface. This is not a "kitchen sink" application with lots of features you may or may not use. If you want a clean, easy-to-read data display to complement your navigation and weather apps, this might be the one for you. Also works very well on iPads and other tablets, including "split screen" mode so you can use other navigation apps side-by-side. And the Apple Watch lets you keep track of course, speed and essential data, hands free, no matter where you are on your boat!