An intuitive, easy to use tactical mobile application for sailors by sailors. Built and optimized for iPhone and Apple Watch. Maximum feedback with minimal user input. Easy to use interfaces with highly visible displays. Distance to line, tactical pre-start data, and a race dial that tracks wind shifts and headers! We are happy to announce that all these features are also available on the Apple Watch. At tack X, our mission is simple. First, we provide sailors clear and concise data in all conditions. Second, we foster the improvement of sailing skills and a lifetime of learning through technology. Not only do we write and test the software for our customers, we use it too. Every member of our team uses tack X. Our continuous field testing process means a better experience for you. Not a racing sailor? Not a problem there are features for you too! Use the nav display for position and course information. Use the "line manager" to calculate distances and times to coordinates. And more! Features for all devices: - Easily readable user interfaces with large, clear fonts optimized for viewing in bright sunlight even with polarized lenses - Time your start to a tenth of a second - Track your distance to the start line - Pre-start course guidance and tactics - Track wind shift lifts and headers - Line length, seconds to run line, seconds to line - Map view - Manual boat and pin input - Signal K for NMEA integration - Apple Health App integration - add to your daily exercise goal while you sail - Night Mode - Diagnostics - And much more ******** DOWNLOAD THE USER GUIDE ******** Available at the developer & support URL. Before leaving a review - please contact us at the support link - we are here to help! We are constantly improving tack X. We have many features planned for upcoming releases. If you have a feature you want to see let us know! *Note that this app uses your location in the background. Using location background mode may dramatically decrease battery life.