Looking for a Sailing Logbook App With an Anchor Alarm? NaviLog Questions Answered

Free or paid, offline or not, Android or iPhone, and where your logbook data ends up.

When sailors look for a logbook app, the same questions come up every time. Here are straight answers for NaviLog, the offline sailing logbook with an anchor alarm and a barograph, so you can decide quickly whether it fits your boat.

What is NaviLog?

NaviLog is a digital ship's logbook for skippers. It records your trips by GPS, stands anchor watch with a physics-based swing circle, marks a man-overboard position with one tap, and draws a barograph from your phone's own barometer. It runs on Android and iPhone, in English and German.

Who is it for?

Sailors, skippers, charter crews, motorboaters and liveaboards — for coastal cruising, blue-water passages, regattas, sailing school and logging miles for a licence.

Is NaviLog free?

Yes. The full logbook, GPS tracking, the anchor alarm, MOB, the barograph and storm alarm, seamarks and night mode are free, without ads and without a time limit.

What does Pro add?

Pro is a single one-time purchase — no subscription — that adds:

• PDF logbook (with a barograph page) and sea-miles certificates
• GPX export for OpenCPN and chart plotters, CSV import and export
• Optional cloud backup across your devices
• Crew lists and checklist templates
• Offline chart download

The price is shown in the app store for your country. Bought Pro on one device? A second device with the same store account recognises it automatically.

Does it work without internet?

Yes. Tracking, the anchor watch, MOB, the barograph, the storm alarm and downloaded chart regions work completely offline. Only weather forecasts, place names and new map tiles need a connection.

How does the anchor alarm work?

You set where the anchor lies and enter chain length, water depth, bow height and boat length; optionally tide range, mooring type, a second anchor or a swing sector. NaviLog computes the real swing circle from that, instead of a guessed radius. It has a pre-alarm, a separate GPS-loss alarm and a low-battery warning, and you can adjust the anchor position or chain length while the watch stays armed.

Does the anchor alarm work on iPhone?

Yes, with one limit: Apple restricts what apps may do in the background, so on iPhone the anchor alarm is only reliable while NaviLog stays open on screen. The app keeps the screen awake and tells you this when you arm the watch. On Android the watch runs all night with the screen off. On both: keep the phone on charge.

What if my phone has no barometer?

Then the barograph and the pressure-based storm alarm aren't available; NaviLog detects that and tells you. Everything else works as usual, and online weather forecasts still work. Most iPhones and many Android phones have a barometer.

Does NaviLog drain the battery?

Tracking and the anchor watch use GPS sparingly, and the barometer is read in short bursts. The app warns you when the battery gets low. For an overnight anchor watch, plug in anyway.

Do I need an account?

No. NaviLog works without an account. You only sign in if you switch on cloud backup (Pro), and you can delete that account from inside the app.

Where is my logbook data stored?

On your phone, in a local database. If you switch on cloud backup, trips, checklists and tracks are also backed up privately to your account. No ads, no tracking of your behaviour, no selling of data. Deleted trips stay in a trash for 30 days.

Can I get my data out?

Yes, with Pro: the whole logbook as PDF, tracks as GPX (one track per day), and trips, crew, yachts and the anchor archive as CSV, which you can also import again.

Can it produce sea-miles certificates for a licence?

Yes. NaviLog creates a sea-miles certificate from your logged trips as a PDF (Pro). Check with your licensing authority which form of proof they accept.

Is NaviLog a chart plotter?

No. It shows OpenSeaMap seamarks over OpenStreetMap and your recorded tracks, but it's not for route planning or navigation. Use OpenCPN or a dedicated plotter for that. NaviLog is your logbook and your watchkeeper — an aid to good seamanship, not a substitute for it.

I run a charter company or sailing school. Is there something for us?

Yes: NaviLog Fleet adds a digital check-in and handover to the same app — QR sticker on the boat, mandatory photos, checklist, damage report and signature, and a PDF report by e-mail. Skippers use it for free. See navilogfleet.ch.

Where do I get it?

• Android: Google Play
• iPhone: App Store
• Website: navilogfleet.ch
• Contact: [email protected]

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