Comparison

ChronoLog vs ClockSync

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

ChronoLog

This app provides professional-grade tools to track the accuracy of mechanical watches. It offers audio timegraphing, photo offset measurement, and tap timing, along with detailed analytics and atomic time synchronization for collectors and enthusiasts.

Highlights
  • 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
Features
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ChronoLog — Timegrapher, Watch Accuracy Tracker & Collection Log Turn your iPhone into a timegrapher. ChronoLog listens to your mechanical watch through the microphone and reads its rate in seconds per day — then keeps measuring over days and weeks, on your wrist, so you know how the watch really runs, not just how it ran on the bench. No subscription. No account. One-time purchase unlocks everything. AUDIO TIMEGRAPHER • Rate in seconds per day from your watch's tick, in about 30 seconds — the same number a timegrapher gives you. • Every reading carries a confidence score, so you know when to trust it and when to record again. • Movements from 18,000 to 36,000 bph, detected automatically or set per watch. ACCURACY OVER TIME — THE PART A TIMEGRAPHER CAN'T DO A bench reading captures one moment. ChronoLog logs every measurement into timing runs and charts the daily rate as you actually wear the watch: watch it drift, catch magnetization, and see when it needs regulation or a service — before it costs you minutes a week. • Photo offset: photograph the dial against atomic time for the most precise manual reading. • Tap timing: tap on the second for a quick log with any watch, quartz included. • Tag measurements by position, temperature or activity to learn what moves the rate. ACCURACY REPORT — NEW A health score for every watch, timekeeping trends per run, and an anonymous comparison against the same models worldwide — find out whether your Submariner or your SKX keeps time better than most. Share a private report link that expires on its own. ATOMIC TIME Every measurement is referenced to NTP atomic time, not your phone's clock. Use the live atomic clock, with an optional seconds tick, to set your watches to the second. YOUR COLLECTION, ORGANISED • Unlimited watches with photos, brand, model, calibre, serial number, service history and notes. • Wear log: swipe to mark what you're wearing, then see your rotation as a calendar, timeline and stats. • Moon phase: last and next full moon with the days between — set a moonphase complication in seconds. • Full backup and restore. CSV export for your records or your watchmaker. WHY COLLECTORS CHOOSE CHRONOLOG A timegrapher is for adjusting a watch. ChronoLog is for knowing it — clean, fast, ad-free, built by a collector in Boulder, Colorado, who reads and answers every review. Download ChronoLog and find out how your watches really run.

About

ClockSync

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ClockSync allows you to discover and configure nearby Xiaomi LYWSD02 / MJWSD05 clocks. You can adjust the time, the time zone, and the units used for temperature. This is an unofficial app, and is not supported or endorsed by Xiaomi.

Screenshots

ChronoLog4 screens
ClockSync3 screens

Verdict

The call

The clearest difference is price: ChronoLog at Free against ClockSync's $0.99. ChronoLog also leads on iOS requirement (15.0 vs 26.0). ClockSync's advantage is in-app purchases (none vs 2). On update cadence, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

ChronoLog is free to download; ClockSync costs $0.99 up front. ChronoLog sells 2 one-off in-app purchases. ClockSync asks for nothing beyond the download.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 3 weeks. The most recent releases landed on November 3, 2026 and November 5, 2026 respectively.

Scorecard3 real differences · 7 level
ChronoLog versus ClockSync: the parameters behind the verdict, then further details
ParameterChronoLogClockSync
PriceFree — better$0.99
Rating4.6 (236 ratings) — better—
Positive reviews85.0% of reviews—
Number of ratings236 — better—
Update frequencyEvery 3 weeksEvery 3 weeks
AdsNoNo
In-app purchasesYesNo — better
MonetizationPaid—
DevicesiPhone, iPad, iPodiPhone, iPad, Mac
Requires iOS15.0 — better26.0
Further details — not scored
Size50 MB4 MB
Age rating4+4+
Developertyler woodElegant Chaos Limited

In-app purchases

2 purchases

ChronoLog

One-time2
  • Premium$5.99
  • Premium$6.99
None

ClockSync

No in-app purchases

Questions

Is ChronoLog free?
ChronoLog is free to download, with in-app purchases available.
Is ClockSync free?
ClockSync costs $0.99, with no in-app purchases.
Do ChronoLog or ClockSync have ads?
Neither ChronoLog nor ClockSync shows ads.
Which is updated more often, ChronoLog or ClockSync?
ChronoLog ships an update every 3 weeks, and ClockSync every 3 weeks. Most recently, ChronoLog was updated on November 3, 2026 and ClockSync on November 5, 2026.

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