Timegrapher — Watch Accuracy

No subscription, ever. Measure rate, amplitude and beat error in 30 seconds, track every watch you own, and see what it's worth — with the first watch free forever.

A timegrapher in your pocket: rate, amplitude and beat error from your iPhone's microphone in 30 seconds. Reads through room noise, with amplitude computed from your calibre's own lift angle. First watch free — Pro is one purchase, never a subscription.

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 a watchmaker checks first • Beat error — the tick/tock asymmetry that says the escapement wants adjusting • Beat rate — detected automatically, from vintage 18,000 bph to hi-beat 36,000 bph

WHY THE READINGS HOLD STEADY Phone timing apps have a reputation for jumping around, and for amplitude you can't trust. Two things are done differently here. The analyser tracks the room's own noise floor and rejects transients, so a quiet movement stays locked on — it will read a watch through a barking dog. And amplitude is computed from the lift angle you set for that specific calibre, because a wrong lift angle is the single most common reason a phone app reports the wrong swing.

Each tick is really three tiny impacts. Timegrapher times every 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 machine.

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

TRACK WHAT IT'S WORTH One tap pulls current Chrono24 asking prices for your exact reference and logs the median — computed on your device, in your own currency. Log what you paid and Timegrapher charts each watch's value over time, its gain since purchase, and your collection's total.

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

PRICING Your first watch is free, forever. Timegrapher Pro unlocks unlimited watches for a single payment — no subscription. Purchases restore on any device signed into the same App Store account.

HONEST LIMITS A quiet room and firm contact between phone and case give the best readings. Results are indicative: a bench machine and a professional's judgement remain the gold standard for service decisions.