You can watch vessels in a browser on your phone or laptop, or use the AIS Fleet app for iPhone. Both use the same account. The app also connects to an AIS receiver on your local Wi-Fi, if you have one; no receiver is needed to watch vessels from the network.

Getting it

The app is in open beta through TestFlight. Features may change between updates, and feedback is welcome. Joining takes two steps, both free.

1. Install TestFlight, Apple's own app for trying apps before they reach the App Store, from the App Store.
2. Open the AIS Fleet beta invitation and tap Accept. The link is on the aisfleet.com sign-in screen, on the map once you are signed in, and in the e-mail that brings you your sign-in code.

Sign in with the same e-mail address you use on the website and enter the new six-digit code sent to you. Your follows, fleets, messages and photos belong to that account and carry across devices.

The app requires iOS 17 or later and is designed for iPhone. There is no dedicated iPad layout yet. On iPad or Android, you can use aisfleet.com in your browser; there is no Android app at present.

Open TestFlight to install updates. If a build has expired, install the latest available build there. If TestFlight offers no build or the invitation is unavailable, use the website and contact [email protected].

If you would rather not be reminded about the app, the note on the map has a close button, and closing it stops it coming back.

What the app does that a browser cannot

The app reads an AIS receiver on your Wi-Fi and draws the reports directly. This works aboard a boat or with a receiver ashore. The website cannot connect directly to that receiver.

Connect a receiver

1. Join the Wi-Fi network the receiver uses, usually your boat's network.
2. Open You > AIS receivers. Read the sharing notice: connecting a receiver also contributes its reports to AIS Fleet when internet is available.
3. Choose Scan this network and allow Local Network access when iOS asks. Pick a receiver the scan finds.
4. If it is not found, choose Add manually. For TCP, enter the receiver's address and port. For UDP, choose a listening port and set the receiver to send to the iPhone address shown on that screen. Use Test connection, then Save.

If access was denied, enable AIS Fleet under Settings > Privacy & Security > Local Network on your iPhone. If a UDP connection stops after a router restart, check the iPhone address again; it may have changed.

While receiving

• A successful connection can be quiet. "NMEA data, no AIS yet" means data is arriving, but no vessel reports have been decoded yet. Check that the receiver is forwarding AIS and give it time to hear a vessel.
• What it hears is drawn on the same chart as the rest of the traffic, with a lighter outline on the marker, so you can tell "my aerial heard her" from "the network heard her". Where both have her, the fresher position wins.
• Not everything it hears is a ship. Navigation marks, including the virtual ones, base stations and search and rescue aircraft get marks of their own rather than being drawn as boats. Distress beacons get an alarm mark that no filter can hide.
• A boat goes off the chart when her class says she should have reported and has not, rather than being left where she was last seen. A fast target held for ten minutes would be drawn miles from where she is.
• It receives while the app is open and on screen. Locking the phone or switching apps pauses reception. Keep the screen on while receiving, under AIS receivers, can help when you want to leave the chart open; it uses more battery.

A receiver you connect also contributes what it hears to AIS Fleet, which is how the map gets its coverage in places no shore station reaches. There is deliberately no separate switch for this: a receiver that is on is a receiver that is contributing, and turning the receiver off is what stops it. Your phone appears in My Stations on the website as a station of its own, private to you. Share your AIS receiver is the whole story, including what you grant by sharing.

Without internet

The local receiver connection can keep working on Wi-Fi without internet. Network vessel updates, search, messages, sign-in and sharing reports with AIS Fleet need internet access. Chart tiles that have not already loaded may be missing, so this is not an offline chart package. Network requests and contributed reports use whichever internet connection your phone has available, which can include mobile data.

Receiving AIS does not make your phone an AIS transmitter: seeing a vessel here does not mean she can see your boat. Use your usual onboard navigation and safety equipment.

What the app does that the website also does

The tab bar is Map, Photos, Messages and You.

• The map is the same one chart, with the same controls down the right: Traffic, your follows, your fleets and Types, plus Fit track while a track is drawn. Tapping a vessel opens her panel as a sheet you can lift with your thumb: a peek showing her name and what she is doing, then the full card. Reading the vessel map
• Search reaches the whole network, the same four ways.
• Track history draws where she has been, over the window your plan allows.
• Photos shoots or picks a picture and sends it, with the same question about the location saved in the file. Vessel photos
• Messages carries direct and fleet conversations, with attachments and reactions. Messages
• Notifications is the same feed, with the same per-boat settings.
• Lists are in the app: the panel with a switch per list, adding a boat from her own sheet, making a list, its settings, and subscribing to a public list somebody shared. Your follows and your lists are the same set on both. Lists
• Claiming your boat works in the app: MMSI, confirm, upload the document. Claim your boat
• Plans can be bought in the app, as App Store subscriptions, with Restore purchases if you change phone. Plans and billing explains why it matters where you bought one.

What still lives in the browser

Open the website with the same account for these tasks:

• My Stations. Adding a receiver that is not on your phone, reading a station's statistics, setting where a shore receiver listens from, switching one off: all on the website. Share your AIS receiver
• Starting and running a fleet. You can be in a fleet in the app, read its roster and its chat, and leave it. Creating one and managing its boats is on the website. Fleets
• The distance row, and a fleet's notice rows. The app's list settings carry the departure and arrival switches. Choosing the distance for a nearby notice, and a fleet's notice rows, are on the website for now. Departures and arrivals

One thing opens in a browser on purpose rather than by omission: the note that invites a boat's owner to claim her carries her MMSI into the claim wizard, and that route is browser-only so an installed app cannot swallow the number. Messages

Notifications on your phone

If something is wrong

Write to [email protected], or reply to an AIS Fleet e-mail. Include your device, iOS version, app build from TestFlight, the screen you were using and what happened. For a receiver problem, include its model and whether you used TCP or UDP. Please leave sign-in codes and receiver credentials out of your report.