Nav Rules: COLREGS Quiz

See a cluster of lights across dark water and instantly know what that vessel is — and who has to give way. Nav Rules turns the COLREGS rules of the road into a quiz you can actually practice, from night light identification to give-way encounters.

▶ NIGHT LIGHT ID QUIZ — a rendered silhouette shows the lights and shapes of a vessel; you name the type. Powered, sailing, towing, fishing, anchored, restricted and more.

▶ GIVE-WAY ENCOUNTER ENGINE — set two vessels at any relative angle and the app tells you which is give-way and which is stand-on, with the exact rule number behind it.

▶ RULE REFERENCE — plain-language summaries of the key steering and sailing rules, plus lights and shapes, available offline.

▶ SOUND SIGNALS — the whistle and horn signals for maneuvers, overtaking and restricted visibility, in one quick reference.

▶ FULLY OFFLINE — everything works without a signal, out on the water or studying at the dock. No account.

Great for boaters brushing up, license and exam candidates, sailing students and anyone who wants to read the water at night with confidence.

IMPORTANT: This app is a study aid and reference, not for actual navigation. It is not a substitute for the official rules, proper training or a qualified lookout. Always consult the current official COLREGS and follow the direction of a competent authority when underway.