Dutchman's Log
Measure water boat speed
$2.99 · Designed for iPad. Not verified for macOS.
Utility to measure your boat speed over the water. Can also be used to calibrate or to check accuracy of your speed/log device.
A boat's speed may be estimated by timing how long the boat takes to pass a floating object.
The boat length and desired units must be entered in 'Settings'
Two persons are needed, one stands on the bow and the other aft.
The person on the bow throws an object that will float (crumpled piece of paper) into the water, ahead and to one side of the bow.
As it passes the bow at right angles, they shout 'Now', and the person on the stern taps the 'start timing' button.
When the object passes the stern at right angles, the 'stop timing' button is tapped.
The App now calculates and displays the boat speed.
Units in Knots, metres/second or Kilometres/hour
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Improved performance
Updated user interface
The developer, Navtech Software, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Colin Porteous
- Size
- 1.3 MB
- Category
- Navigation
- Compatibility
Requires iOS 18.1 or later.
- iPhone
Requires iOS 18.1 or later. - iPad
Requires iPadOS 18.1 or later. - Mac
Requires macOS 15.1 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 2.1 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2026 Navtech Software
