These are the iOS apps I use when sailing.
Do you have a favorite app for sailing and cruising that’s not listed here? Leave a comment below and share with us!
 |  | Anchor Good anchor watch utility. I recommend keeping the phone plugged in and charging while using this. Even better, use the Vesper Cortex for the purpose instead. Update June 2023: This app appears to be unavailable. |
 |  | Boat Beacon Shows vessel AIS on a map. This is not an AIS transceiver; AIS data comes from the internet. As a result, this app only works when you have internet coverage. And only those vessels are shown which are in range of a terrestrial or satellite AIS receiver. Finally, the app does not transmit any AIS information. This app is not a substitute for an AIS transceiver, but it can be handy in a pinch. |
 |  | BoatUS Handy app to have installed if you subscribe to the BoatUS towing service. |
 |  | CBP One App for accessing U.S. immigration and customs services. |
 |  | CBP ROAM App for accessing U.S. immigration and customs services. |
 |  | Coast Guard Handy app for accessing U.S. Coast Guard information, reporting hazards, and emergency assistance. Update June 2023: This app appears to be unavailable. |
 |  | CrowdMag Can be used to determine magnetic variation anywhere on Earth. |
 |  | DiDi Rider Rideshare app used in some countries, most notably Mexico. |
 |  | Earth Class Mail Access your postal mail if you subscribe to the Earth Class Mail service. See also Top Ten Lifestyle Tools for Sailors, Cruisers, and Other Nomads. |
 |  | find my way back now I use this to remember (and later find!) locations of things when traveling… where the dinghy is parked, where the car is parked, the turns made on an unmarked hiking trail, etc. |
 |  | Google Voice Convenient telephony services while traveling. See also Top Ten Lifestyle Tools for Sailors, Cruisers, and Other Nomads. |
 |  | Knots 3D Reference for how to tie various knots. |
 |  | Maps.me A mapping & navigation app that can be used offline when cell service is spotty or unavailable. |
 |  | Marine Barometer Shows barometric pressure. Note that this requires a phone with a barometric pressure sensor. |
 |  | Navionics Boating I don’t like the app, but the Navionics data is good for showing detailed sea floor contours in anchorages, so I use this in addition to my usual chart sources when piloting an anchorage. |
 |  | Ocean Atlas Presents very recent climate data—such as prevailing winds, avg/max wind speed, avg/max wave height, historical cyclones, etc.—on map. Think interactive pilot chart. Useful for passage planning. |
 |  | Photos PDF : Scanner Converter Scans your documents to go paperless and eliminate papers getting wet. See also Top Ten Lifestyle Tools for Sailors, Cruisers, and Other Nomads. |
 |  | PredictWind Access to weather forecasts. This app requires internet connectivity. |
 |  | PredictWind Offshore Access to weather forecasts. Can be used offshore over an Iridium GO! device. Requires a paid subscription. |
 |  | SEAiq Quite frankly the best navigation software I’ve found on iOS and macOS. Not free, but very much worth the price. |
 |  | Star Pilot Performs celestial navigation computations. Great for learning or double-checking your sight reductions. |
 |  | Tide Graph Pro A great tidal forecast tool for U.S. locations. |
 |  | True Wind Calculator to convert between true and apparent wind. |
 |  | Weathermuffin A novel marine weather forecast app which, based on your position, course, and speed, quickly and proactively tells you about adverse conditions to look out for. Includes data not seen elsewhere, such as wave steepness, confused seas, and lightning. Also shows NOAA synoptic weather charts (i.e. weather fax) overlaid on the map. Can be used offshore with an Iridium GO! device. Some features require a paid subscription. |
 |  | WhatsApp A communications tool useful for keeping in touch with friends and family while overseas. Also very popular for texting in many countries. See also Top Ten Lifestyle Tools for Sailors, Cruisers, and Other Nomads. |
 |  | Windy Access to weather forecasts. This app requires internet connectivity. |
 |  | World Tides A great tidal forecast tool for locations around the globe. I’ve found it to be accurate in the places I’ve used it. |
 |  | Zulu Time A nice display of UTC time regardless of the time zone set on the phone. Useful for celestial navigation sights and other purposes. |