Maritime Master OOW

Maritime Master OOW is a serious study companion for Officer of the Watch candidates and working deck officers. It brings together the calculators, references, and revision tools you need for watchkeeping exams and orals, then adds personal logs so you can track your progress toward certification.

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Everything is organised the way a deck officer thinks: navigation, rules, watchkeeping practice, regulations, communications, and emergencies, each a couple of taps away when you need to check something quickly or settle a mess-room debate.

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Calculators for Deck Officers

Work through navigation problems with speed, course, and distance, estimated time of arrival, dead reckoning, position fixing, and set and drift tools. Terrestrial navigation covers compass error, parallel indexing, object distance, and advance and transfer.

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A radar plotting assistant supports your plotting practice, while the manoeuvring estimator, mean draft, trim, and vertical centre of gravity calculators cover ship handling and stability. Meteorological tools include true wind, barometer correction, and Beaufort conversion, plus a full set of unit converters.

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A Watchkeeping Reference Library

Revise the full COLREGs with sound signals and day shapes, IALA buoyage, navigation lights, semaphore, and signal flags from the International Code of Signals. Study summaries of SOLAS, MARPOL, STCW, the ISM Code, and the ISPS Code alongside safe watchkeeping practice, bridge resource management, logbook guidelines, and standing orders.

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Electronic navigation content covers ECDIS functions, AIS data interpretation, AIS codes, and MMSI numbers, while safety sections span GMDSS, VHF channels, radio frequencies, emergency procedures, and SOPEP. Bridge equipment and handover checklists help you learn the routines that good watchkeeping depends on.

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Track Your Sea Time

Log voyages and sea time, and follow your OOW progress tracker as certification approaches. Your records live in your own private iCloud account where only you can see them, and home screen widgets keep ship data, upcoming voyages, sun times, and Zulu time a glance away.

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Test Yourself

Sharpen up with exam question sets from fifteen to sixty five questions, flash card packs, and recognition games that make lights, flags, and buoyage automatic. It is the kind of little-and-often practice that makes orals feel familiar.

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Downloads and Premium

A growing library of downloadable PDF study documents, including radar plotting sheets, is built in. Many are free, and a single one-time premium unlock opens the full set. There is no subscription.

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Who It Is For

Built for OOW candidates, deck cadets, and qualified officers keeping sharp between contracts. All tools and content are for training, study, and revision only, not for real-world navigation or operational use, and personal logs do not replace official records.

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Part of the Maritime Master Family

Pair it with Maritime Master Radar for hands-on ARPA practice, Maritime Master COLREGs for a deep dive into the rules, and Maritime Master CalcDeck for the full professional calculator library.

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Frequently Asked Questions

Is there a subscription? No. The app is a one-time purchase, and an optional one-time premium unlock adds the full document library. Nothing renews.

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Is my sea time data private? Yes. Voyages and sea time entries are stored in your personal iCloud account. We cannot see or access them.

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Does the sea time log replace my official logbook? No. It is a personal reference to help you track progress. Official records must always be kept through the proper channels.

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Get Maritime Master OOW on the App Store for iPhone and iPad and make every watch a study opportunity.