Horology

Know how your watch is really running.

Rest a mechanical watch against your iPhone or iPad. Horology listens to the beat and shows its rate, beat error and amplitude, each with a tolerance, in about a minute.

Works offlineNo accountNo ads or tracking

Horology measuring a watch: locked at 21,600 bph, with rate, amplitude and beat error above a live waveform and the timegrapher trace

Every screen

One app, laid out for each device

Horology on iPhone: a display case of five watches with the Measure button below

Horology on an unfolded iPhone Duo: watch details on the left and the display case on the right

Horology on iPad in landscape: watch details on the left and the display case on the right

What you see

Honest numbers

Rate

Seconds per day

How fast or slow the watch runs, with a tolerance so you know how far to trust it.

Beat error

Milliseconds

How evenly the escapement ticks and tocks.

Beat rate

Recognised automatically

From 12,000 to 36,000 beats per hour, no setting to get wrong.

Amplitude

When it's clear

Shown only when the sound is clear enough to read it.

Trace

The classic display

Ticks and tocks as two rows of dots: flat means true, climbing means fast, sinking means slow.

First run

A guided start

Add your first watch and measure it in about two minutes, or try the built-in sample recording.

Horology waits until it has locked onto the beat before it shows a number, stops by itself when the reading is steady, and tells you if the rate moved. If it can't hear the watch, it shows you where to place it instead of guessing.

In the app

Your collection, at a glance

A display case with five watches — Your collection

Horology finding the beat — Finding the beat

A locked measurement with the timegrapher trace — Measuring

Performance over time chart — History and charts

The guided start highlighting the first slot to tap — Guided start

Pricing

Free to measure. Pro to track.

Measuring is free and unlimited. A one-time Pro purchase adds reading history, charts, CSV export and more than one case. No subscription, no ads. Everything stays on your device.

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