What it does
- Scope from the bow roller downThe old ratios forget where the rode begins. Rainbow’s End Anchoring measures from your bow roller to the seabed at the worst point of the night — tide and surge included.
- Recommends from your own lockerEvery anchor and rode you carry, scored for tonight’s bottom and wind. When the plan needs gear you don’t have, it says so instead of pretending.
- Five ways of lying, plus stormRegular anchoring, a mooring ball, Med mooring, lines ashore, and a Bahamian moor — each with its own geometry — and a storm mode with a two-anchor plan.
- Honest chain physicsKnow the wind at which your chain pulls bar-taut, the angle at the anchor, and what a few more feet would buy you.
- Warnings that name the problemThin margin, wrong anchor for the ground, not enough water at low tide — in words, not just numbers.
- An anchor watch, and a watch from ashoreMark the drop and the app fences the swing from tonight’s plan, plots the night north-up, and sounds an honest alarm on a real breach. Leave a device aboard sharing, and any other device on your Apple ID can monitor her through your own iCloud — with an alarm if she breaks out, or goes quiet.
- Entirely offlineNo account, no signal needed, and nothing you enter ever leaves your phone. Built for anchorages, which rarely come with bars. The remote watch is the one opt-in exception, and it talks only to your own iCloud.
- Every boat you step aboardKeep your own boat, a charter, and the dinghy as separate profiles, each with its own tackle — in your own words, down to naming the lunch hook.
- Your unitsFeet, meters, fathoms, shots, or your own rode marks. Depth in what the instrument reads, answers in what the windlass counts.
Rainbow’s End Anchoring is an aid to judgment, not a substitute for it. Its holding figures are estimates drawn from independent testing, presented as estimates — and if an answer ever disagrees with your seamanship, trust your seamanship.
Rainbow’s End Monitor
A free companion app for the people who sail with you. With the watch armed, the boat can share it under an eight-character code — and anyone who types that code into the Monitor sees the same fence, the same plot, and hears the same alarm, on their own phone. No account, no Apple ID in common, and nothing of theirs goes anywhere.
- The watch, on the crew’s phonesThe fence around her anchor, where she lies inside it, and an alarm if she breaks out — or falls silent, because a link that has gone quiet must never look like a boat riding safely.
- Find her from the dinghy dockOne arrow points at your boat, with her bearing and distance beneath it, and her name, hull color and photo so you can tell her from the boat next door. It still points when there is no signal.
Coming to the App Store for iPhone and iPad. The crew never control the boat: no disarming, no silencing her alarm, no touching the fence.
Rainbow’s End Provisioning
Provisioning for sailors, from a day sail to an ocean passage. Plan every meal of the voyage on a calendar, mark what’s eaten ashore, say who drinks what and which allergies are aboard — and the calendar becomes the grocery list: every meal’s ingredients times the crew, minus what’s already in the lockers, rounded up to real packs. Print it for the crew or take it to the store on your phone.
- The charter pattern, built inFull provisioning or split — breakfasts and lunches aboard, most dinners ashore — and meals underway lean to one pot a cook can manage in a seaway.
- Arithmetic you can checkYou can’t buy 13 eggs, so it buys 18. Fresh food planned past its keeping window is flagged; so is a meal someone aboard can’t eat, with an alternative — never struck from the menu.
On the App Store for iPhone and iPad — formerly Rainbow’s End Galley. Fully offline: nothing leaves your phone unless you print or export it yourself, or switch on iCloud sync to keep your own iPhone and iPad the same. More about Provisioning.
Rainbow’s End Manifest
The book of your boat: what the Coast Guard requires aboard, where it’s stowed, the briefing your guests hear, the log of where she’s been, and the schedule that keeps her fit. All of it derived from your vessel. All of it on your device.
On the App Store for iPhone and iPad. Fully offline; optional sync through your own iCloud. More about Manifest.
Rainbow’s End Float Plan
Leave word ashore before you leave the dock. A float plan tells someone reliable exactly what to say to rescuers if you don’t come home; this app fills one out with you and hands you a PDF made to be emailed.
On the App Store for iPhone and iPad. Fully offline; the plan leaves your device only when you send it. More about Float Plan.
More
- Support & FAQSetup, how the numbers work, and how to report one that looks wrong.
- Privacy PolicyShort, because the app collects nothing.
- Rainbow’s End Monitor — SupportThe free crew companion: joining by code, the alarms, finding the boat.
- Rainbow’s End Monitor — Privacy PolicyCollects nothing; your position stays on your phone.
- Rainbow’s End ManifestThe book of your boat.
- Rainbow’s End Float PlanLeave word ashore before you leave the dock.
- Rainbow’s End ProvisioningProvisioning for sailors, from a day sail to an ocean passage.
- Rainbow’s Arc PositioningA camera sextant, for the fun of it.
Designed by Rainbow’s End Marine. Apps for sailors, by sailors.
May you find a rainbow’s end and treasure found wherever you sail or set your anchor.
© 2026 Rainbow’s End Marine, LLC · support@RainbowsEndMarine.com · www.RainbowsEndMarine.com