Isochron: Watch Accuracy
Timegrapher & watch tracker
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
Your iPhone is now a timegrapher. Measure any mechanical watch in 30 seconds — rate, beat error, amplitude — and see how it compares with every other owner’s.
Rest your iPhone against your watch and watch its rate appear live — like a bench timegrapher, without the bench.
MEASURE LIKE A WATCHMAKER
• Daily rate (s/day) and beat error in about 30 seconds, with a live scrolling beat trace
• Amplitude from your caliber’s true lift angle (Pro)
• Guided position tests with a chronometer-style report (Pro)
• Overnight stability runs — drift across the power reserve (Pro)
• Magnetism check using your iPhone’s sensors (Pro)
MEASURE LIFE ON THE WRIST
A bench reading tells you how a watch runs on a table. Isochron’s photo method tells you how it runs on your wrist: photograph the dial, we timestamp it against atomic time, and the drift between photos is your real worn accuracy.
YOUR COLLECTION, DOCUMENTED
Every watch with photos, specs, serials, full accuracy history, service records, warranty reminders, wear rotation — and a polished PDF insurance report (Pro).
COMPARE WITH EVERY OTHER OWNER
Your reading lands on the live distribution for your exact model and movement. Better than 84% of Submariner owners? Now you know. Then talk shop in caliber-specific forum boards.
FAIR PRICING, NO SUBSCRIPTION
Measuring, your collection, the photo method, and the community are free — forever. The bench instruments are one single purchase. No subscription, ever.
PRIVATE BY DESIGN
Audio is analyzed on-device and never uploaded. No ads, no tracking.
IAP — Isochron Pro: “Isochron Pro” / “Amplitude, position tests, overnight runs, magnetism check, and the insurance report. One purchase, yours forever.”
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
The developer, Seth Adam Mundall, 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 Linked to You
The following data may be collected and linked to your identity:
- Contact Info
- User Content
- Identifiers
- Other Data
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- User Content
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Seth Adam Mundall
- Size
- 3.1 MB
- Category
- Utilities
- Compatibility
Requires iOS 17.6 or later.
- iPhone
Requires iOS 17.6 or later. - Mac
Requires macOS 14.6 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.3 or later.
- iPhone
- Languages
English and 5 more
- English, French, German, Italian, Japanese, Simplified Chinese
- Age Rating
4+
- 4+
- Contains
Messaging and Chat
User-Generated Content
- Copyright
- © Seth Adam Mundall