Mark Time is an application for Celestial Navigation that solves the problem of how to take an accurate time reading to go with each sextant sighting.

By simply tapping the screen you can record the exact time UTC as you take your sight, so you have no chance of making an error with the conversion, and this time is stored in one of five registers.

Very useful when you have an assistant, and ideal for taking readings when you are on your own.

As you record a time you hear a confirmation sound and feel a vibration, so there is no need even to look at the screen. In addition the actual latitude and longitude at each time can be accessed later to verify your calculations. These options are all configurable in Settings to suit your own preferences.

You can optionally take a photo of your sextant at the marked time so that you can read your sextant or confirm your reading later. Pinch and zoom to get a really close look at the scale.

What’s New

Version 1.1

Take a photo of your sextant at the marked time, so you can check easily double-check your reading.
Pinch and zoom on the photo to get a really close look at the scale.
Delete one of the 5 stored readings if you have tapped by mistake.


Sarah Reichelt
10.3 MB

Requires iOS 11.4 or later. Compatible with iPhone, iPad, and iPod touch.



Age Rating
Rated 4+
Copyright © 2019 TrozWare.


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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