Rainbow's End Marine
Anchoring
Know your swing. Trust your ground tackle.
The old scope ratios forget where the rode begins. Anchoring measures from your bow roller to the seabed at the worst point of the night — tide and surge included — and recommends tackle from the gear you actually carry.
Why it stands out
Different by design. Honest by doctrine.
Scope from the bow roller down.
Most calculators measure from the bow. Anchoring measures from the bow roller — the actual start of your rode — to the seabed at the worst point of the night, tide and surge included.
Recommends from your own locker.
Every 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 storm.
Regular 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 physics.
Know the wind at which your chain pulls bar-taut, the angle at the anchor, and what a few more feet of scope would buy you.
What it does
Built for the questions you actually ask at sea.
Anchor watch with a real alarm.
Mark 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 — not a GPS hiccup.
Remote watch via iCloud.
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.
Warnings that name the problem.
Thin margin, wrong anchor for the ground, not enough water at low tide — in words, not just numbers.
Every boat you step aboard.
Keep 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.
What it won't do
What the app won't do is a feature.
Anchoring will not tell you the ground is good. It works from your entered depth and bottom type — it cannot feel the seabed.
It will not silence the alarm automatically. A breach is a breach until you decide otherwise.
It will not make the call for you. The holding figures are estimates, presented as estimates. If an answer ever disagrees with your seamanship, trust your seamanship.
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.
Available now
Anchoring is live on the App Store.
Available for iPhone and iPad. No account, no tracking.
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