Boat & Gear
The electronics that tell you where the boat is and warn you when it moves: chartplotters, GPS and AIS, navigation apps like Navionics, and the anchor alarm built into your plotter or watch versus a dedicated app — compared honestly, including ours.
18 guides
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Every app that does the job, compared on the things that matter at three in the morning.
Read the guideNine anchor alarm apps side by side: which phones they run on, what they really cost in the App Store, which ones let you watch the boat from ashore, and what each is called in the store. Includes the one everybody searches for that turns out not to be an anchor alarm at all. One of the nine is ours, and it says so.
October 10, 2026
The Navionics Boating app has no built-in anchor alarm — the Anchor Drag alarm people search for lives on Garmin chartplotters. Where the confusion comes from, why the track workaround can't wake you, and the chart-app + alarm-app setup most cruisers run.
July 11, 2026
Garmin, Raymarine and B&G chartplotters all ship an anchor alarm — so is a phone app redundant? Where each plotter hides the setting, why the alarm circle is centred on the boat instead of the anchor, and the primary-plus-backup setup most cruisers run.
July 12, 2026
The anchor watch is a duty, not a device — and a GPS app is just another way of keeping it. Where a phone beats a human watchkeeper (attention that does not fade, position instead of guesswork, an alert that reaches a sleeping crew), where it is no use at all (weather, the neighbour dragging down on you, a chafing snubber), and how to set the watch so it is worth trusting.
August 17, 2026
See your anchor safe radius and distance from the anchor right on your Apple Watch. How a wrist-based anchor alarm works, how to read it at 3 a.m., and why it's the quietest way to keep watch overnight.
July 2, 2026
GPS is a utility on a boat, not a product: five or six receivers aboard all hear the same satellites, and what differs is the antenna's view of the sky, the update rate and the screen the fix lands on. GPS versus GNSS, what WAAS and EGNOS correct, dual-frequency phones, the Wi-Fi iPad that has no GPS at all, plotter antennas, handhelds and Bluetooth pucks in one accuracy table, chart datum, and which fix the anchor alarm should use.
October 4, 2026
How accurate is phone GPS for anchor monitoring? Understand the difference between harmless GPS drift and real dragging, why anchor alarms false-trigger, and how to set your alarm radius so it only wakes you when it matters.
June 30, 2026
You don't need thirty apps — you need one great app for each job at sea. The essential toolkit organised by job: charts, weather, anchorages, anchor alarm, tides, AIS, routing, trip logging, the boat's maintenance records and safety tracking. Two of the eleven are ours, and they are marked.
August 24, 2026
A combo is two instruments sharing one screen, and the sonar you get is decided by the transducer, not the inches. How to read 93sv, Elite FS 9 and Helix 9 MSI+, where a combo ends and an MFD begins, which chart card is in the box, 2026 prices, and why the sounder is the half that matters at anchor.
September 30, 2026
The screen is a strip chart, not a photograph: the right edge is now, the depth is measured from the transducer until you set a keel offset, and the bottom is read by the thickness of its line and the second echo, not its colour. Sand, mud, rock and weed decoded, arches versus lines, 50 kHz versus 200 kHz versus CHIRP, the five settings worth touching, and the two-minute circle with the sounder before every anchor drop.
October 1, 2026
The VHF is a broadcast, not a phone: the boat two miles off hears you before the coastguard does. Channel 16 and the working channels, the licence and MMSI question, the exact Mayday, Pan-Pan and Sécurité formats, and the handheld in the grab bag.
September 26, 2026
Marine VHF is line of sight: range is 2.2 times the square root of the antenna height, at each end, added together, and watts only make the voice clearer inside that circle. A range table for handhelds, rails, mastheads and coastguard aerials, why a heeling sailboat wants 3 dB and a powerboat 6 dB, how much signal RG-58 throws away, the SWR test, AIS splitters, and the handheld on the cockpit table at anchor.
October 2, 2026
AIS is a VHF broadcast of who you are and where you are going, and the classes differ in how they get a turn to speak: Class A and Class B+ reserve a slot, plain Class B waits for a gap and in a crowded harbour may not get one. The three transponders and the receiver side by side, reporting rates by speed, what a ship's bridge sees of you and the status field it never gets, the MMSI and where it comes from, who must carry AIS, 2026 prices, and the AIS at anchor.
October 3, 2026
The MMSI is the boat's phone number: nine digits that belong to the vessel, not to you and not to the radio, sent by the red button to the coastguard and by the AIS to every ship in range. What the digits encode and the country codes, the free US routes (BoatUS, US Power Squadrons) and the $220 FCC licence a boat needs before the Bahamas or Canada, the UK, Canadian and Australian routes, why the radio accepts the number once, what to do when a boat or a radio changes hands, how to look an MMSI up, the Coast Guard's 90% / 60% finding, and the number at anchor.
October 6, 2026
Radar sees what is actually there: the unlit fishing boat, the dragged buoy, the squall. How it works, what the range on the box really means, pulse vs solid-state, the six controls, why the overlay needs a heading sensor and not GPS, radar vs AIS, reflectors, and the guard zone as a second anchor watch that can see other boats.
September 27, 2026