tcSpeeds vs Hull Speed

tcSpeeds provides advanced knowledge of your current speed, average speeds, maximum speed, directional speeds, velocity made good, wind measurements, and much more. You will be able to measure your performance on a straight course with our proprietary Pilot Performance Index (PPI) computation. Compare how good you are at the controls with your friends or against your autopilot. tcSpeeds stands on its own and does not require external hardware or connections to operate. tcSpeeds uses your device's own internal GPS, accelerometers, and compass. For Wind measurement, you will need to acquire the Calypso Ultrasonic Wind sensor. More sensors will be supported in the future. Easy to use and conceived to minimize operational burden on the user, because we know you have other things to do. Zero setup required: install, launch and tap the start button. Designed for iPhones, and GPS-equipped iPads. CAPABILITIES - Add waypoints on the map - Apple watch extension - auto-VMG Velocity Made Good automatic detection - Add, move, or edit you waypoint location on the map - Cross track to waypoint indicator - Record and save your track - Start Line guide for speed and heading when you race - VMG automatic maximum VMG to waypoint - VMG visual assistant: guides you to the best course to the waypoint on the current tack - Maximum VMG indicator relative to waypoint - Audio alert for Acceleration and maximum speed: get instant feedback for you and your team when you are doing it right - Apple Watch Extension: Speed, Course, VMG, Cross-Track, Display remote control and more - Arrival Time: smart computation using filtered VMG averages - Barometer indicator on supported devices - Pilot Performance Index (PPI) calculation improvement - Speed indicator with color-scaled plot - Directional speed vectors panel with automatic polar graph - Maximum speed keeping - Maximum speed audio and visual alarms - Trip distance recording - Add, move, edit Waypoints - Accurate sub-second timer - GPS status with location accuracy indication - Boxed average speed by timed interval: 10-sec 1-min 10-min 1-hour - Pilot Performance Index (PPI) calculation, measurement, and guide - Target course indicator with automatic and manual fine tuning - Headings, bearings and directional indicators (magnetic/true) - Precise real-time cross track reporting - Course, Compass and proprietary C-Course heading selector - Rapid units selection: metric, nautical and imperial - Situational (non-navigational) map with color-coded speed track - Map display with target course and Look-Ahead-Vector (LAV) - Time and distance to autoscaled LAV endpoint - Velocity Made Good (VMG) relative to Waypoint - Magnetic compass and Course Over Ground (COG) integrated panel - Crab angle and local magnetic declination

Hull Speed is a simple speedometer for sailors. It shows your speed over the water in knots — big, clear, and accurate — on your iPhone and Apple Watch, with nothing else to clutter the display. Built for trimming sails: make a small adjustment, then watch the live trend graph to see if the speed changed. FEATURES • Accurate GPS speed in knots, updated every second, using the same Doppler method as dedicated marine instruments — no paddlewheel to foul or calibrate. • A live speed graph on a steady, fixed scale, so a small gain from a trim change is easy to spot. • Enter your boat's waterline length and Hull Speed draws your theoretical hull speed right on the graph — see at a glance how close you are to it. • Apple Watch app with a Keep Awake mode that holds the screen on while you sail. • Completely private — your location is used only to compute speed on your device, and is never stored, sent, or shared. No accounts, no ads, no tracking.