Frequently asked questions

It gives you a plain-English read of the sea conditions where you are and where you will be when you arrive, judged against what your own boat finds uncomfortable. You log your position from time to time; the app checks the forecast for now and for your arrival and tells you whether things look OK, are worth watching, or are a concern. It also helps you pick a departure time, find a nearby harbour, and handle a man overboard.

Skippers and crews sailing along the Mediterranean coast, between islands and on day or overnight passages within reach of land and a phone signal. It is not designed for ocean crossings.

No. Use it alongside the official forecast and warnings for your area, your charts and your own judgement. It is a second opinion that is quick to read, tuned to your boat. It is not a navigation aid or a safety system.

The forecasts are global, so the basic checks work anywhere. The emergency contacts, official warning links and harbour notes are written for the Mediterranean.

Nothing needs switching on, and the app does not track you. It only knows your position when you add a fix on the Add fix tab. An hour after each fix, a notification reminds you to add the next one.

About once an hour, or whenever conditions or your plans change. Each fix refreshes the conditions, the distance to go and your arrival time. Between fixes those figures do not update by themselves.

Your position (or tap the GPS button), speed over ground and course over ground in degrees true. True wind angle and speed are optional but let the app check the forecast against your instruments. On the first fix of a passage, add your destination. See Adding a position fix.

All three: decimal degrees (36.8253), degrees and decimal minutes (36° 49.520', as Navionics and most plotters show it) and degrees, minutes and seconds (36° 49' 31.2"). Choose one with the Format buttons above any position. The app remembers it and gives you one box per unit, so you type the position exactly as your plotter shows it, and positions are shown in that format throughout the app. Use the N/S and E/W buttons for the hemisphere. The position is read back under each box so you can check it. See Typing positions.

Yes. Tap Choose destination on map, zoom in, tap the spot, check the position and place name, then tap Use this point. The same works for the arrival point when planning a passage. See Choosing a destination on the map.

Before you leave, tap Plan a passage on the Dashboard and enter your departure and arrival points and times. Check best window scans the next 72 hours for the clearest time to go. Start pre-departure monitoring gives a report for the whole route and reminds you every two hours to recheck, until your planned departure time. The latest report is kept on the phone, so you can still read it offshore with no signal. See Planning a passage.

The app works from your last fix and the speed you gave with it, and measures the straight-line distance. Your plotter updates continuously and may follow a route. The Dashboard shows how old your last fix is. Add a fresh fix to bring the app up to date. More in Common problems.

Tap Arrived - end this trip on the Dashboard when you are in. You do not need to enter a final fix. If you do log a fix within 1.5 nm of your destination, the app also asks whether you have arrived. Either way the fix reminders stop, the trip stays in the Log where you can export it, and your next fix with a new destination starts a new trip.

Yes. Tap Share update on the Dashboard, or Share this update on the pre-departure screen, to send the written report by message, WhatsApp or email.

Every fix is kept in the Log. Tap Export beside a trip to save all of its fixes as a CSV file you can open in Numbers, Excel or Google Sheets, or Export all trips in one file for everything. A new destination starts a new trip, so if an export looks short, check whether the fixes you want are in another trip.

Yes. In the Log, tap Edit on the fix, then Delete this fix. The next fix's progress is worked out again from the fix before.

Concern: waves are at or above your height limit and coming from inside your boat's awkward angle band. Watch: one of those is true, or some information is missing. OK: neither is true. These are about your boat's comfort limits, which you set on the Boat tab. See OK, Watch and Concern.

The range of wave angles, off the bow and off the stern, that your boat handles badly. Many boats, catamarans especially, cope with waves from ahead or astern but struggle on the quarter. For example, a band of 15° to 30° covers waves from 15° to 30° either side of the bow and of the stern. See Your boat profile, and Quartering seas, and your boat for how waves from different directions affect different boats and how to choose your numbers.

With every fix the app checks how the air pressure has changed over the last three hours. If it is falling quickly (more than 3.5 hPa in three hours) or very rapidly (more than 6 hPa), it adds "A front may be approaching - worth keeping an eye on it." to the barometer line on the Dashboard. It is a prompt to check the official forecast. It does not change the badge or send a notification. See The barometer warning.

Underway, no: conditions are checked when you add a fix or refresh, and the app reminds you to add a fix every hour. At anchor, yes, if you switch on the weather watch. For official warnings, keep a VHF on and check the national weather service.

Forecasts of wind, waves and pressure come from Open-Meteo, which combines several national weather models. Each check is compared with a second model (GFS, from the US weather service), with live wind reports from the nearest airport weather station when one is within reach, and with your own wind instruments if you enter them. The Data sources screen in the app has the details and links to each country's official warnings.

Two sources disagree by a meaningful amount, for example the forecast and a live station, or two forecast models. When forecasts disagree, conditions are less certain, so it is a good moment to look at another forecast.

They often come from different directions, and the waves matter most for how the boat behaves. Wind is the solid orange arrow, waves the dashed purple arrow, and your heading the teal triangle. Tap the button under the compass to switch between north up and course up.

Fetching weather and the map need a connection: mobile signal, Starlink or marina wifi. Your log, boat profile, reminders, the last passage plan report, the man overboard alarm and the marina and harbour search in the Mediterranean work offline. The anchorage search needs a signal the first time you search an area; after that the coastline is saved on the phone. If you save a fix with no signal, the fix is kept and you can re-run the weather check later from the Log.

No. It only goes online when you add a fix, refresh or search, and each check is a few small requests. It does not run GPS in the background, except for the anchor alarm and weather watch while you have them switched on.

It records your GPS position straight away, sounds an alarm, shows a notification and keeps a red banner on screen. The MOB screen shows the course and distance back and lets you share the position. It does not call the coastguard: use VHF channel 16 or DSC and the numbers on the Help screen. See Man overboard.

Tap Help - emergency contacts on the Dashboard. Maritime rescue numbers for Mediterranean countries are listed with the nearest first. Tap a number to call it.

Yes. Tap At anchor on the Dashboard, mark the anchor from the GPS or on a map, enter your chain and a swing radius, and start it. The phone keeps checking its position in the background and sounds an alarm if the boat goes outside the circle. See At anchor.

Yes. Add a no-go sector: two bearings from the anchor and a distance. It is shaded red inside the swing circle, and the alarm sounds if the boat goes into it beyond that distance, as well as outside the circle. Keep the distance at least 15-20 m, because a phone's GPS wanders by 5-10 m. See At anchor.

Yes, by Telegram, if the phone on board has mobile data or wifi. You make a Telegram bot of your own in a few minutes, and the app sends the anchor alarm, weather alarms and a low battery warning to your Telegram chat or a crew group, with the boat's position. If the phone on board loses its signal or switches off, no message is sent, so do not rely on it alone. See Alarm messages on Telegram.

Not automatically. The phone sends the messages itself, so if it loses its signal, runs flat or switches off, it cannot send anything, including a warning that it is offline. In an anchorage with weak coverage, send a test message before you leave, and go back to check if you are unsure. Telegram messages add to your anchor watch; they do not replace it. See Alarm messages on Telegram.

Yes, with the weather watch on the same screen. It sounds an alarm if pressure falls by 1 hPa or more in an hour or 3 hPa or more in 3 hours, or if gusts or waves at or above your limits are forecast for the next 6 hours.

Every 30 minutes suits most nights; 15 or 20 minutes if a front is expected. The phone's own barometer is read every 5 minutes regardless. The checking interval makes little difference to battery, because keeping the GPS running in the background is what uses it. Keep the phone on charge.

Only for the anchor alarm and weather watch, so they keep working with the phone locked. If you say no, they work only while the app is open on the At anchor screen; you can allow it later with the Allow background checks button on that screen. Everything else in the app needs location only while you are using it.

Yes. While the anchor alarm or weather watch is on and the phone is not charging, it warns you at 20% and sounds a louder alarm at 10%, because both watches stop when the phone switches off. The At anchor screen also shows the battery level.

No. There is no account and no sign-in.

Your boat profile, fixes, log and passage plans stay on your phone. To fetch weather and map data, the app sends positions, and nothing that identifies you, to public services: Open-Meteo, aviationweather.gov and OpenStreetMap services (including OpenSeaMap for sea marks on the map). See the privacy policy.

So the GPS button and man overboard can fill in your position, and to sort emergency contacts by distance, while you are using the app. The anchor alarm and weather watch also use it in the background, but only while you have them switched on. Your position stays on the phone. If you decline, you can type positions instead.

Not at the moment, because nothing is stored in the cloud. Export each leg from the Log to keep a copy, and set up your boat profile again on the new phone.

iPhone and iPad, and Android phones and tablets. On a tablet it works in portrait and landscape (and Split View on iPad); on a phone it stays in portrait.

Yes, but each device keeps its own separate log, as nothing is synced between them.

The app is free to download, with a 3-day free trial for new users. After that it is €14.99 a year. For a charter or a short trip there is a 2-week pass for €5.99, which does not renew: it simply ends 14 days after you buy it. Or you can pay €39.99 once for a lifetime unlock with no renewals. Outside the euro area Apple and Google set the equivalent price in your currency, shown on the subscription screen and on the App Store and Google Play listings. Man overboard, emergency contacts, your log and the help pages are always free.

In your App Store or Google Play subscription settings, at least 24 hours before the renewal date. In the app, tap Subscription at the bottom of the Boat tab, then Manage or cancel subscription. If you cancel during the free trial, nothing is charged. You can also turn renewal off straight after subscribing and still keep the full year.

No. Sign in with the same Apple or Google account, open the subscription screen and tap Restore purchases.

Tap Redeem a code on the subscription screen. On Android this opens Google Play's redeem page; when you come back to the app it unlocks.

Yes. The app remembers your subscription and checks it with the store again when it next has a signal. The weather features themselves need a signal to fetch new data.

Apple and Google handle all payments, so refunds go through them. On iPhone, use reportaproblem.apple.com. On Android, use the Play Store's refund request (within 48 hours of purchase), or Google's standard refund process after that.

Email medsailingweather@pm.me with what you were doing, what you expected and what happened instead. A screenshot helps a lot. Much of the app started as a sailor's suggestion.

Yes: the user manual covers every screen with screenshots, and Common problems lists fixes for the issues people meet most often.