# ChronoLog • Watch Accuracy — Accuracy and Timegrapher > Mechanical watch accuracy tracker and audio timegrapher for collectors. (iPhone/iPad app by tyler wood.) - Source: https://appshunter.io/ios/app/chronolog-watch-accuracy/id6452083510 (this page in markdown: same URL + `.md`) - Developer: [tyler wood](https://appshunter.io/developer/1698739777) - Category: Utilities - Price: Free with in-app purchases (on sale, was $4.99) - Rating: 4.70/5 from 198 App Store ratings · 99 written reviews indexed - Age rating: 4+ - Requires: iOS 13.0 · 48 MB - Languages: American English - Released: 2023-08-08 - Data updated: 2026-08-23 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/chronolog-watch-accuracy/id6452083510/reviews.md ## What is ChronoLog? ChronoLog — Watch Accuracy Tracker & Audio Timegrapher for Mechanical Watches Track the accuracy of your mechanical watches with professional-grade tools. ChronoLog combines an audio timegrapher, offset measurement logging, and atomic time synchronization into one app — purpose-built for watch collectors and horology enthusiasts who care about precision. No subscription. No account. One-time purchase unlocks everything. MEASURE WATCH ACCURACY — THREE WAYS • Audio Timegrapher: Use your device's microphone to listen to your watch's tick and measure rate (seconds per day), beat error, and amplitude — the same metrics a professional timegrapher provides. • Photo Offset: Photograph your watch dial against atomic time, enter the displayed time, and ChronoLog calculates the exact offset. The most precise manual method for measuring watch accuracy. • Tap Timing: Tap when your watch hits a specific second to quickly log an offset. Fast, simple, and works with any watch. TRACK ACCURACY OVER TIME Each measurement is logged to a timing run — a series of readings that ChronoLog analyzes together. Monitor your watch's daily rate, see how accuracy changes day to day, and spot regulation issues before they become problems. Tag measurements with conditions like position, temperature, or wear pattern to understand what affects your watch's performance. ATOMIC TIME SYNCHRONIZATION ChronoLog syncs with NTP atomic time servers so every measurement is referenced against true time — not your phone's clock. View the live atomic time, compare it to your device, and use it as a precision reference when setting your watches. DETAILED ANALYTICS & VISUALIZATIONS Dive into performance graphs that show rate trends, offset history, and accuracy patterns across your entire collection. See at a glance which watches in your collection are your most accurate daily wearers and which need regulation or service. BUILT FOR WATCH COLLECTORS • Add unlimited watches with photos, brand, model, serial number, caliber, and notes • Organize your collection with archive support • Export all measurement data to CSV for your records or your watchmaker • Back up and restore your full database across devices WHY CHRONOLOG? Whether you're a seasoned collector checking COSC-grade accuracy, a hobbyist curious about your Seiko's daily rate, or a watchmaker tracking regulation results — ChronoLog gives you the tools to measure, log, and understand your watch's timekeeping performance. Built by a watch enthusiast in Boulder, Colorado. Download ChronoLog and start measuring your watch accuracy today. ## Key features - Audio timegrapher for rate, beat error, and amplitude - Photo offset measurement against atomic time - Tap timing for quick offset logging - Track accuracy trends over time - Atomic time synchronization - Detailed performance graphs and analytics - Manage and organize watch collection ## Pricing and in-app purchases Base price: Free. **One-time purchases** | Purchase | Price | Type | | --- | --- | --- | | Premium | $6.99 | one-time | | Premium | $5.99 | one-time | ## Recent user reviews (10 of 99) All indexed reviews: https://appshunter.io/ios/app/chronolog-watch-accuracy/id6452083510/reviews.md ### 5/5 — Best app I’ve tried yet to track my watches *2026-08-22, version 2.5.0* This app pretty much does all you could ask: logs your wear time, tracks your watches accuracy by both manual input and the ability to take a picture, as well as work as a Timegrapher which admittedly I haven’t tried that feature since I have an actual Timegrapher. The other feature are pretty much flawless and the app is laid out extremely user friendly. I really like the fact that it gives you stats on what watch you wear the most/least, most recent, and what hasn’t been on your wrist in a long time. Just buy this app you won’t be disappointed ### 1/5 — Keine Funktion *2026-08-14, version 2.5.0* Geräusche angeblich zu leise - ist eine Standuhr, die man einen Raum weiter noch hört…😆 ### 4/5 — Bisher die beste App zum Thema *2026-08-08, version 2.5.0* Ich habe sämtliche Apps zum Funktionsumfang „Dokumentation der Sammlung“, sowie „Vermessung der Sammlung“ im AppStore getestet (inkl. Premium Funktionen) und muss sagen diese App hier ist der beste Allrounder. Es gibt Apps, bei denen die KI Automatismen eventuell etwas akkurater treffen, aber das ist eine absolut sekundäre Funktionalität. Bei der Abweichungsdokumentation ist das Ergebnis hier übersichtlich gestaltet und schnell erfasst. Gerade bei größeren Sammlungen leidet die Übersichtlichkeit bei der Konkurrenz stark. Positiv nennen muss man hier auch die Update-Politik, denn die kommen oft, bzw. regelmäßig mit sinnigen Verbesserungen. Die Audiomessung funktioniert inzwischen auch super. Was ich mir da allerdings noch wünschen würde, wäre dass das dot-Protokoll mit Beat-Error und Amplitude auch nach der Erfassung noch einsehbar ist - es bleibt leider nur der ermittelte Wert ersichtlich, den Rest muss man direkt nach der Erfassung mit einem Screenshot speichern, sonst sieht man es nie wieder - deshalb einen Stern Abzug. Ein weiterer Verbessungsvorschlag wäre noch, das man zum verwendeten Gerät eventuell eine Grafik hätte, mit der man die genaue Position des zur Audiomessung verwendeten Mikrofons einsehen kann. Das bekommt man zwar auch mit einer Internetrecherche heraus, aber gerade neuen, oder technisch unbedarften Nutzern würde man so den Weg zu einem genaueren Ergebnis bereiten. ### 3/5 — Nu recomand *2026-08-03, version 2.5.0* După câteva folosiri a început să nu mai “audă” microfonul telefonului (semnal slab), deși microfonul nu are nici o problemă. A devenit inutilă… ### 1/5 — App Does Not Know What a Watch Sounds Like *2026-08-02, version 2.5.0* I cannot recommend ChronoLog. My biggest complaint is with one of the app’s headline features: using your phone’s microphone to analyze the sound of a mechanical watch. Apparently, the algorithm does not have a firm grasp on what a watch actually sounds like. As a test, I repeatedly said the word “click” into my phone’s microphone, gradually speeding up as the session went on. ChronoLog dutifully analyzed my performance and eventually reached the conclusion that I was not speaking at all—I was, in fact, the proud owner of a catastrophically defective mechanical watch. According to the app, my entirely fictional timepiece was beating at roughly 18,000 BPH and losing about 1 hour and 32 minutes every single day. I admire the confidence. Faced with the choice between “this person is obviously talking” and “this is the worst watch ever manufactured,” ChronoLog committed to the latter. The app never stopped to ask the obvious question: “Could this possibly not be a watch?” Beyond that, I struggle to see the value in many of the other features, especially now that the app has abandoned its free trial in favor of an upfront purchase. Take the newly released “Wear Log.” Every time you put on a watch, you tell the app. Every time you take it off, you tell the app again. In exchange, the app rewards you with an exquisitely detailed historical record confirming that, yes, you wore your watch. Curious which watch you wear most often? Unable to glance down at your wrist over the course of several weeks and form even a vague impression? ChronoLog has a painstaking, manual, bespoke workflow for exactly that. The app feels less like a tool for watch enthusiasts and more like an experiment in seeing how many ordinary activities can be converted into data entry. If future updates teach the microphone the difference between a mechanical escapement and a guy saying “click” over and over, I’ll happily give it another look. ### 5/5 — Great App. Great Price. *2026-07-28, version 2.5.0* Amazing app. Does what all the other apps do but more for so much less money. This app/tool is worth so much more than the $4 one time payment. Other apps charge a monthly fee of like $6 but do less than this and that just crazy. My favorite features are the ability to see the movement of the watch in 3D and the vibration clicks per seconds help me set the accuracy so well. 10/10 app. If you’re a watch enthusiast or even just starting the hobby I couldn’t recommend this app more. ### 5/5 — Best Customer support ever. *2026-07-23, version 2.4.1* At the beginning the application did not work perfectly but after contact with Tyler started working as expected. Strongly recommended. ### 3/5 — Fee *2026-07-18, version 2.4.1* you should just make the app paid from the beginning instead of forcing you to pay to continue using it. ### 5/5 — Výborná aplikace *2026-07-16, version 2.4.1* Po poslední aktualizaci došlo k výrazné vizuální změně aplikace, vypadá výborně. Došlo i k opravám chyb a přidání nových funkcí - super, jen tak dále. Splňuje veškeré funkce které jsem hledal. Přesný čas pro seřízení, evidenci (specifikace, datum i cena pořízení) a měření pro vícero hodinek. Dokonce mohu i sledovat jak často které hodinky nosím :-) Možnostmi aplikace jsem překvapen a velice potěšen. ### 5/5 — Thoughtfully Designed, Sleek App *2026-07-16, version 2.4.1* Makes it easy to log my watch every morning, as far as I can tell it’s very accurate. Support small developers and buy this app! Well worth the money. ## Frequently asked questions about ChronoLog ### What does ChronoLog do? ChronoLog is an app designed to help you track the accuracy of your mechanical watches. It provides professional-grade tools like an audio timegrapher, photo offset measurement, and tap timing to measure your watch's performance. It also allows you to log and analyze these measurements over time, offering insights into your watch's precision. ### How does the audio timegrapher feature work? The audio timegrapher uses your device's microphone to listen to the 'tick' of your mechanical watch. It then analyzes this sound to measure key metrics such as the rate (seconds per day), beat error, and amplitude. These are the same metrics professional timegraphers use to assess watch accuracy. ### What is the cost of ChronoLog? ChronoLog is a one-time purchase application. There are no subscriptions or recurring fees required. Purchasing the app unlocks all features, providing full access to its watch accuracy tracking and analysis tools. ### What devices is ChronoLog compatible with? The app description does not explicitly state compatibility requirements. However, as it utilizes a device's microphone and camera for its features, it is likely compatible with most modern smartphones and tablets running a recent version of their respective operating systems (iOS or Android). ### Who would benefit from using ChronoLog? ChronoLog is built for watch collectors, horology enthusiasts, and even watchmakers. Whether you are a seasoned collector aiming for COSC-grade accuracy, a hobbyist curious about your watch's daily rate, or a watchmaker tracking regulation results, this app provides the tools to measure, log, and understand your watch's timekeeping performance. ## Version history (last 5 releases) ### 2.5.0 — 2026-07-24 What's new in 2.5.0: • Redesigned Wear Log — browse your wear history in new Calendar, Timeline, and Stats views, with a live banner for the watch on your wrist • New watch details: record production year and purchase condition • Quickly scroll through large collections with the new scrollbar • Optional ticking sound for the Clock • Refreshed Settings and Manage Data screens • Safer backups: restores are now validated, and a snapshot is saved automatically first • A refined new app icon • Plus various fixes and polish throughout the app ### 2.4.1 — 2026-07-07 Fixing some bugs and some forms ### 2.4.0 — 2026-06-17 This update sharpens ChronoLog into an even better timegrapher for your mechanical watches. • Redesigned audio measurement screen — read your watch accuracy at a glance with a cleaner live view of rate (seconds/day), beat error, and amplitude. • New two-line beat trace — watch every tick land in real time as ChronoLog listens to your movement. • Per-measurement notes — record position, service, or conditions alongside any reading. • 3D Movement Explorer — orbit a mechanical movement in interactive 3D. • Smoother camera setup for photo measurements, plus polish throughout. Measure watch accuracy, regulate with confidence, and keep your mechanical watch collection running on time. ### 2.3.1 — 2026-06-12 2.3.1 fixes bugs in 2.3.0! From 2.3.0 Update: The biggest Chronolog update since launch. Watchbox redesign • New card design with hero watch images, inline rate + offset, and a live sparkline trend. • Toggle comfortable vs. compact density from the tab bar. • Sort by brand, seconds-per-day, last measured, or last worn — the order updates live as your data changes. • Swipe right to wear, left to archive or delete. Restore archived watches from the new Archive sheet. Timing & service • Per-run notes from any run's ••• menu — record position, conditions, or anything worth remembering. • Service history: track when each watch was serviced, with add / view / edit from the watch's edit sheet. • Refreshed onboarding with clearer guidance on Tap, Photo, and Audio measurements. Graphs • Redesigned offset graph — colored lines per timing run with audio overlaid in gold, matching the rate graph. Wear tracking • Edit past wear sessions, add backdated entries, and use the new Least Recent tab to spot watches overdue for wear. Premium chrome • Time Sync, Manage Settings, and Wear Log modals refreshed with consistent title bars, brass section labels, and matching action pills. • Streamlined watch summary modal: new title bar, tighter edit form, instant save. • Cleaner Close affordance on the measurements modal and a tighter onboarding preview that fits smaller screens. • Add Watch now captures a purchase currency code. Cloud sync • One-way device → cloud backup with batch sync and queue replay (gated by feature flag). Other • Richer CSV export now includes run notes, watch notes, and a service history section. • Purchase currency persists correctly across app launches. • Spanish language support added. ### 2.3.0 — 2026-06-09 The biggest Chronolog update since launch. Watchbox redesign • New card design with hero watch images, inline rate + offset, and a live sparkline trend. • Toggle comfortable vs. compact density from the tab bar. • Sort by brand, seconds-per-day, last measured, or last worn — the order updates live as your data changes. • Swipe right to wear, left to archive or delete. Restore archived watches from the new Archive sheet. Timing & service • Per-run notes from any run's ••• menu — record position, conditions, or anything worth remembering. • Service history: track when each watch was serviced, with add / view / edit from the watch's edit sheet. • Refreshed onboarding with clearer guidance on Tap, Photo, and Audio measurements. Graphs • Redesigned offset graph — colored lines per timing run with audio overlaid in gold, matching the rate graph. Wear tracking • Edit past wear sessions, add backdated entries, and use the new Least Recent tab to spot watches overdue for wear. Premium chrome • Time Sync, Manage Settings, and Wear Log modals refreshed with consistent title bars, brass section labels, and matching action pills. • Streamlined watch summary modal: new title bar, tighter edit form, instant save. • Cleaner Close affordance on the measurements modal and a tighter onboarding preview that fits smaller screens. • Add Watch now captures a purchase currency code. Cloud sync • One-way device → cloud backup with batch sync and queue replay (gated by feature flag). Other • Richer CSV export now includes run notes, watch notes, and a service history section. • Purchase currency persists correctly across app launches. • Spanish language support added. ## Apps similar to ChronoLog | App | Rating | Price | Category | | --- | --- | --- | --- | | [Twelve O'clock](https://appshunter.io/ios/app/twelve-oclock/id1570977980) | 4.4 (82) | Free | Utilities | | [TickTracer - Watch Accuracy](https://appshunter.io/ios/app/ticktracer-watch-accuracy/id6474094486) | 4.3 (9) | Free | Utilities | | [Timegrapher - watch accuracy](https://appshunter.io/ios/app/timegrapher-watch-accuracy/id6450460771) | 2.8 (44) | Free | Utilities | | [EMF & Magnetic Detector](https://appshunter.io/ios/app/emf-and-magnetic-detector/id1403751803) | 4.6 (417) | Free | Utilities | | [Watch Tuner Timegrapher](https://appshunter.io/ios/app/watch-tuner-timegrapher/id991367080) | 3.8 (74) | $7.99 | Utilities | | [Magnetized Wristwatch Checker](https://appshunter.io/ios/app/magnetized-wristwatch-checker/id6478119877) | 4.6 (21) | Free | Utilities | ## Related topics [watch accuracy](https://appshunter.io/ios/topics/watch-accuracy) · [watch accuracy meter](https://appshunter.io/ios/topics/watch-accuracy-meter) · [watch accuracy checker](https://appshunter.io/ios/topics/watch-accuracy-checker) · [watch regulator](https://appshunter.io/ios/topics/watch-regulator) · [chronolog](https://appshunter.io/ios/topics/chronolog) · [watch amplitude](https://appshunter.io/ios/topics/watch-amplitude) · [automatic watch](https://appshunter.io/ios/topics/automatic-watch) · [mechanical watch](https://appshunter.io/ios/topics/mechanical-watch) · [watch chronometer](https://appshunter.io/ios/topics/watch-chronometer) · [watch tracker](https://appshunter.io/ios/topics/watch-tracker) · [magnetized wristwatch checker](https://appshunter.io/ios/topics/magnetized-wristwatch-checker) · [toolwatch](https://appshunter.io/ios/topics/toolwatch) · [chronology](https://appshunter.io/ios/topics/chronology) --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-23.*