TenderTo 1.2.1 Get the app

Version 1.2.1 on the App Store

The little app to get you back to your big boat.

Leave your yacht in daylight and return after dark to a crowded anchorage. TenderTo keeps the saved Home Vessel, your track, speed, and tides visible on iPhone—and puts distance, bearing, and a heading-relative arrow on Apple Watch.

Download on the App Store See Apple Watch

Designed by a cruising sailor for cruising sailors.

29° 53.123′ N 081° 19.372′ W ACCURACY ±3 m
2:09 PM L 0.4 ft now
SPEED 4.2 KNOTS
TRIP 1.28 NMTOTAL 5.06 NM
TenderTo sailor duck app icon

Useful when it matters

Built for the ride back after dark.

In a crowded anchorage, the yacht you left in daylight can disappear into a field of anchor lights. TenderTo keeps one verified Home Vessel position at the center of the trip.

01

Daylight navigation

Large GPS coordinates in degrees and decimal minutes, speed in knots, a high-contrast chart, and an enlarged position view for urgent communication.

Explore dinghy navigation
02

Your way home

Save the Home Vessel position, see the straight-line distance back, and keep the return point with the trip until the dinghy is safely aboard.

Learn about the return point
03

Every dinghy trip

Record track, speed, location, distance, and ashore walking as one outing. Correct the On Water or Ashore status manually whenever automatic surface evidence is unconfirmed.

See how trip tracking works
04

Tides and daylight

See a nearby NOAA tide curve, sunrise, and sunset. Tap through to compare the three closest prediction stations and their distance from the tender.

Read about tides and daylight
05

Your tender record

Keep the tender, vessel, motor, registration, owner, and photo details together on the iPhone for quick reference.

Prepare a tender record
06

A report when needed

Create a shareable PDF with identification details and photos if the tender is stolen or others need to help locate it.

See what the report contains

Apple Watch companion

Your way back, right on your wrist.

Set and verify Home Vessel on the iPhone before leaving. On the return ride, Apple Watch keeps the saved vessel direction available at a glance—especially when darkness turns a crowded anchorage into a wall of nearly identical lights.

  • See speed in your chosen navigation units.
  • See direct distance and bearing to the saved Home Vessel.
  • Follow an arrow that rotates relative to the Watch’s current heading.
  • Keep the vessel name, Home Vessel position, and units synchronized from iPhone.

TenderTo is a supplementary navigation aid. Keep a lookout and use proper charts, lights, communications, and independent navigation equipment.

Download on the App Store

From the water

Practical guides for dinghy rides.

Notes from designing and testing TenderTo aboard—written for the situations cruising sailors actually encounter between the yacht and shore.

NavigationA clearer iPhone and Apple Watch displayGPS position, speed, charts, and the direction back to your vessel. TripsKeep the ride and walk ashore togetherOne useful record from departure until the dinghy returns. ReturnMark where the yacht is before leavingA saved Home Vessel point and distance back to the boat. PlanningCheck tides, sunrise, and sunsetNearby predictions kept visible while you navigate. RecordsBe ready if a tender goes missingIdentification details and photographs in a shareable PDF.

From the pond

The latest from TenderTo.

Release notes, work in progress, and the occasional wandering rubber duck.

In testing ·

Small drifts deserve a number, too.

The next GPS update focuses on showing a usable speed promptly, including a gentle half-knot drift. We’re also improving how iPhone and Apple Watch explain uncertain readings and share troubleshooting records.

Automated checks have passed on both platforms. On-water verification is still ahead; these changes are not yet in the App Store release.

Available now ·

Version 1.2.1: ducks in a row. Mostly.

Our little rubber ducks scattered across the pond again. This release gives interrupted trips clearer labels and marks the recording phone’s last saved position and time, so a duck on yesterday’s map doesn’t pretend to know where you are today.

It also includes speed-display and iPhone–Watch consistency improvements. Further GPS refinements are being tested above.

Get TenderTo 1.2.1 →

TenderTo is a supplementary navigation aid. Keep official charts, independent navigation equipment, and good seamanship aboard. No rubber duck has been promoted to captain.

Built in the open

A small community can make a real difference.

Version 1.2.1 is on the App Store, and I’ll continue publishing TenderTo’s progress here as the app improves.

0

Early testers

People helping shape a more useful tender companion.

$0

Raised for medical expenses

Direct support that keeps me going—and keeps TenderTo moving.

94

Development builds

Frequent improvements, tested aboard and ashore.

Last updated September 2026

About the sailor behind the app

Hi, I’m Ewan.

Like you, I am a cruising sailor, and the person designing, building, and testing TenderTo. I’ve built this app to support life aboard, from anchorage to anchorage, to help you reach the shore, explore it, and return home to the boat.

Version 1.2.1 is available on the App Store. I’m continuing to develop TenderTo one practical feature at a time, based on real trips and real feedback from the water.

Read Ewan’s storysupport@tenderto.appSee our progress
Ewan aboard a sailing yacht
Aboard
Ewan resting in a hospital bed
In hospital

Why I built TenderTo

I wanted to leave the cruising community something useful.

Ever leave your boat in daylight, go ashore for adventures, and then struggle to find it in a crowded anchorage after dark? Ever leave the boat in bright sunshine, then have a fog bank roll in and not know where your boat is? Ever cut your time at the beach party short because the sun is going down and you’re concerned about finding your way back to your boat safely? TenderTo is for you.

I was recently diagnosed with heart failure. Instead of starting a GoFundMe, I decided to build something practical for the community that has given me so much joy—in the hope of leaving you with a tool you can use.

The iPhone keeps the full map and recorded route visible. On Apple Watch, a heading-relative arrow, bearing, and distance keep the saved Home Vessel direction available at a glance during the ride back.

If TenderTo adds value to your dinghy rides, you can help me pay my medical expenses by sending a contribution through Venmo.

You keep me going through this medical crisis. I keep adding features and enhancing this tool.
Support @ewanoleary on Venmo QR code for @ewanoleary on Venmo

TenderTo principles

What guides the work.

Readable first.

Information should survive glare, motion, and a wet ride.

Useful offline.

Important trip data stays with you; tide forecasts are cached.

One tender, one vessel.

Keep the everyday setup straightforward.

Honest limits.

Keep independent navigation and safety equipment aboard.

Important limitations

Use TenderTo as an aid—not your only plan.

Navigation.

Keep proper charts, a lookout, lights, communications, safety equipment, and good seamanship aboard.

GPS and Home Vessel.

GPS can be inaccurate or unavailable, and an anchored vessel can swing or move. Confirm the saved position visually.

Surface detection.

Apple can confirm recognized water. Near shore or on land, the surface may remain unconfirmed; use the manual On Water or Ashore control. Speed is never used to guess.

Charts, tides, and daylight.

Map and NOAA information may be incomplete, delayed, or unavailable. Predictions are not real-time conditions.

Emergencies.

TenderTo does not provide collision avoidance, distress calling, rescue coordination, or a guaranteed route home.

Responsibility and liability.

You are responsible for safe operation and for verifying every position, route, chart, tide, and app output. To the fullest extent permitted by law, TealShift, LLC, TenderTo, and its developer disclaim liability for loss, damage, injury, or other consequences arising from use, inability to use, misuse, user error, app error, or inaccurate, incomplete, delayed, or unavailable data.

Questions? Email support@tenderto.app. See the Privacy Policy.