Timegrapher — Watch Accuracy

Why pay a watchmaker to tell you how your watch is running? Rest your iPhone against the case and get rate, amplitude and beat error in 30 seconds — from your sofa.

You don't need an expensive watchmaker — or a $200 bench machine — to know how your mechanical watch is really running. Timegrapher turns your iPhone into a professional timing instrument. Rest the phone against the watch case, wait half a minute, and read the results. From the comfort of your home.

WHAT IT MEASURES • Rate — seconds gained or lost per day, the number a chronometer certificate is built on • Amplitude — how far the balance swings, the vital sign watchmakers check first • Beat error — the tick/tock asymmetry that says the escapement needs adjusting • Beat rate — auto-detected, from vintage 18,000 bph to hi-beat 36,000 bph

HOW IT WORKS Each tick of a mechanical watch is three tiny impacts. Timegrapher hears them through the microphone, times each one to a fraction of a millisecond, and fits thousands of them against your iPhone's clock — the same principle as a watchmaker's bench timegrapher, with serious noise rejection built in (it reads a watch through a barking dog). The live trace draws the classic two sloped lines while you watch.

YOUR COLLECTION Add every watch with photo, reference and serial number, year and lift angle. Every measurement is saved; charts show the rate drifting over months and years, so a movement that's slowly going off gets caught early. After each measurement you get a plain-language health verdict — Excellent to Service needed — with the reasons spelled out, plus a Guide tab that explains every number in plain English.

TRACK WHAT IT'S WORTH One tap pulls the current Chrono24 asking prices for your exact reference and logs the median — computed on your device. Log what you paid (to the year, month, or exact day) and Timegrapher plots each watch's market value over the years, shows its gain since purchase, and sums up the collection at a glance: average age, total value, average gain. Your prices and notes never leave your iPhone.

PRIVATE BY DESIGN Everything runs on the device. No audio is ever recorded, stored or uploaded. No account, no ads.

The first watch is free, forever. Timegrapher Pro — a one-time purchase, no subscription — unlocks unlimited watches. Purchases can be restored on any device signed into the same App Store account.

A quiet room and firm contact between phone and case give the best readings. Results are accurate, but indicative — a bench machine and a professional's judgement are still the gold standard for service decisions.