Searching is how you get to one particular vessel rather than to whatever is passing. Use Search boats, beside the account icon on a computer and behind the magnifying glass at the top of the screen on a phone.

The four ways to search

Type at least three characters; one or two is too little to search on, and the box says so rather than telling you nothing matched.

• A name is the way in for most people, and it is enough on its own. You do not need a number to follow a vessel.
• An MMSI is the nine-digit number assigned to a vessel's radio identity. All nine digits find its record, which helps distinguish boats with the same name. Check the vessel details too: a radio can be programmed with an incorrect number. You will find a boat's MMSI on her radio licence and on many vessel-tracking sites.
• A call sign is the short radio identifier a vessel is licensed under, a mix of letters and numbers.
• An IMO number is a permanent seven-digit number carried by larger commercial ships. It stays with the hull even if she is renamed or reflagged, which makes it the reliable way to follow one particular ship across a change of name.

Call signs and IMO numbers widen a search. Both are reported by a minority of vessels, so a search on one can come back empty for a vessel that is visible on the chart. If that happens, search her name.

Reading the results

Each result carries what you need to tell two vessels of the same name apart: her type, her length, her flag, the water she is in, and how far away she is and in what direction.

• Distance is measured from your own boat when one is linked to your account and has reported recently, and otherwise from the middle of the map you are looking at. The results say which of the two they used. Where the only position available is too old to be useful, the distance is left off rather than guessed.
• A badge on a row says why it is there when there is a reason: Your boat, Following, Fleet-mate, or Saillogger for a boat that keeps her logbook there and shares it. Those rows are lifted up the list, so an exact number match comes first, then the boats you already have a connection with, then everything else by how well the name matches.
• Opening a result takes the map to that vessel and opens her panel. On the website the map zooms in close around a vessel at rest, so she stands out from the boats near her, and a little wider around one under way, so more of the water around her is in view. Opening a boat keeps a closer zoom you chose until another map action changes it.
• A vessel nobody has heard from lately is still returned, labelled with how long ago that was. Opening her takes the map to the position she last reported, and her panel says when that was.
• Results come twenty at a time, with Load 20 more under them and a line saying how many matched. Past two hundred it stops counting and says so; a narrower search works better than paging through.
• Not every result is a ship. Navigation marks, base stations and search and rescue aircraft broadcast on the same system and land in the same list. Where a row is one of those, it says what it is instead of naming a vessel type.

When a search comes back empty

• "No boats match that." Either the name she broadcasts differs from the one you typed, or no receiver has ever reported her to us. Try a shorter, more distinctive piece of the name; if you can get her nine-digit MMSI, searching that gives a definite answer either way.
• "We are not tracking MMSI ... yet." The number is a valid one and we have never had a report for it. Follow it anyway asks the network to watch for it, and on the website she is followed once she is heard. If the vessel is not there
• If search says it is paused, a short-term limit on searches has been reached, and it says nothing about the vessel. Wait a moment and try the same words again; it is not the same thing as no match.

What her panel tells you

Tap a vessel and her panel opens with what AIS reports about her.

• Who she is, in the line under her name: her MMSI, what kind of vessel she is from the type she broadcasts, her AIS class and her flag. For a transmitter that is not a ship, such as a navigation aid, the line says what it is instead. On the website, a known vessel type stays visible if her full details cannot load.
• Her flag. This is the country whose authority issued her MMSI, which is usually but not always where she is registered. For most vessels it is worked out from the first three digits of the MMSI, which is how it can be shown for boats that have never sent us a full identity report; where a vessel has reported her flag herself, that is what you see.
• Her speed and her course, as last heard.
• Whether she is moving or stopped, and where. When she is in a named sea, bay or strait, such as the North Sea, its name follows.
• When she was last heard. The number to read: everything above it describes the moment of that report, not this moment.
• Her destination and ETA, on the vessels that send them, with the note Set by her crew. They are where she says she is going and when she expects to arrive, shown in your time zone. Her crew types both in by hand, so read them as a note rather than a fact. Her destination and ETA arrive with her voyage details rather than with each position report, so they can be older than the time she was last heard. A long-past ETA is left off.
• Her navigational status, alongside her destination and ETA when it adds to her status line. This is the state her crew has set, such as under sail, engaged in fishing or towing; not under command means she cannot manoeuvre as she normally would. These states appear only while she is moving, since a status set on board can stay unchanged after she stops. An active distress beacon is also shown when stationary. On the website, it updates as new reports arrive. Boats with a Class B transponder, which covers most leisure boats, do not send destination, ETA or navigational status.
• Her length and beam, which is how long and how wide she is, and her draught, how deep she sits in the water, on the vessels that send it. Her draught is also part of her voyage details and may update separately from her position. When AIS Fleet has no length or beam for her, the panel says Not reported in its place: her transponder may not send them, or no report with them has reached AIS Fleet yet.
• Her call sign and IMO number, on the vessels that send them.

On the website, the details appear on separate lines when the screen is narrow or text is enlarged, so names and numbers remain readable.

Her status line is based on her recent reports, not on a single report. She stays under way until her reports show that she has stopped, so one report without movement in the middle of a crossing does not mark her as stopped and then under way again. That is why the line can say she is under way while her speed reads zero: the speed is the last figure AIS heard, and the status is what her recent reporting adds up to. When a place name is available, the line names where she is once she is confirmed there, or where she left from while she is on passage. If a place name is unavailable or being refreshed, the line can say Moored or Underway without one. Further reports can supply a name; her map position and last-heard time remain based on the reports received.

Her panel does not list the ports she has called at before.

Boats that log with Saillogger

Some owners share a journal, their boat's photo and the logged track of their current passage. Boats that log with Saillogger explains these extras and how an access password affects them.

The actions on her panel

On the website, the action buttons sit below her speed and status, before her voyage details, dimensions and photos. If your station heard her, the station note appears below the buttons.

• Follow starts the notices and puts her on Favorites. Follow your first vessel
• Add to list puts her on any other list of yours, and reads Add to fleet or list once you run a fleet, with your fleets listed first. Lists, Fleets
• Message needs a reachable boater on the other end, and most vessels on the chart have no linked account to write to. Messages
• Add photo sends a photograph of her to the shared catalog. Vessel photos
• Her photos open full screen, with the count on the cover so you know how many there are.

Choosing what reaches you

Following a boat enables departure and arrival notices. Use Notification settings to choose in-app notices, e-mail and, when available, push in the iPhone app for each boat. Departures and arrivals covers the settings, including list notices and muting.

Track history

AIS track history draws where she has been, as AIS heard her, and Fit track frames the whole line.

The panel offers three windows: the last 24 hours on every plan, the last 7 days with Plus, and the last 30 days with Pro. The windows beyond your plan stay visible and say which plan unlocks them rather than disappearing. Tap a window to draw it, tap it again to put the line away.

The line is a record and not a forecast. A trace may hold no approach at all, and a vessel may take a different line next time, or not make that passage again.

The panel collapses to a slim bar when you want the chart back, and the vessel stays selected.