From the first watch added to your collection to predictive diagnostics: this guide covers every screen of the app, every function, every shortcut. It's the same text you find in Profile › User manual, here in printable and shareable form.
The first five minutes with WatchScope. From download to your first watch in the collection, dial photo and spec sheet filled in.
Open the Collection tab and tap the gold + button at the bottom right. Fill in at least make and model — all the other fields (caliber, reference, serial, year, condition) are optional and can be added or edited later from the watch detail screen.
From the add screen, tap the camera icon at the top to choose between the device camera and the system gallery. The first photo becomes the cover in the collection grid; you can replace it any time by tapping the image on the watch detail screen.
The watch's Info tab collects caliber, frequency (BPH or Hz), lift angle, case diameter, water resistance and the manufacturer's declared rate tolerance. Filling in the tolerance enables the in-spec / out-of-spec verdict on every test; the other fields personalise the PDF report and the predictive diagnostics engine.
If your caliber is among the 1,200+ in the catalogue (Rolex, Omega, ETA, Sellita, Seiko, Miyota, Valjoux, Lemania…), BPH and Lift Angle fill in automatically. For vintage calibers not in the catalogue, BPH and Lift Angle are entered by hand.
Quick Test, COSC Test and Calibration: what each function does, how to start it, how to read the results.
Rest the watch flat next to your phone's microphone, in a quiet environment. Open the Analysis tab, pick a duration between 30 and 120 seconds and tap Start. Readings appear after a few seconds — average rate (s/d), amplitude (°) and beat error (ms). Save the session to link it to a watch in your collection.
From a watch's detail screen, open the COSC tab and follow the guided procedure through the 5 positions (CH, FH, 9H, 3H, 6H — the ISO 3159 sequence). Each position records for about 30 seconds; the result computes ADR (average daily rate), Δmax (variation between positions) and the H–V delta. The verdict reports PASS only when all three rules fall within COSC tolerance.
Want to understand where the 5 positions and the ±2 / +6 s/d tolerances come from? Read the COSC Guide.
Calibration maps your microphone crystal's drift against the kernel clock and produces a correction factor applied to every subsequent measurement. From Profile › Calibrate timegrapher, start the 3-minute session in a quiet room.
Recalibrate every time you change external microphone — the factor is tied to the specific hardware capturing the audio.
Rate (s/d) tells you how many seconds per day the watch runs fast or slow; the target is zero. Amplitude (°) measures the balance wheel's oscillation — healthy values fall between 220° and 330°, with 250–290° being the ideal range. Beat error (ms) is the balance wheel's asymmetry; under 1.0 ms is acceptable, under 0.5 ms is excellent.
The Health tab in the Report turns these readings into predictive diagnostics and a service forecast.
Quiet room. A mechanical watch's tick reaches the phone microphone at roughly 50 dB above the noise floor. Any continuous sound — PC fan, fridge, air conditioning, road traffic, dishwasher — raises that floor and "masks" the tick, degrading the peak-tracking step. Close the room, switch off appliances and audio systems, and avoid resonant surfaces such as glass or metal tables (they can amplify the vibration of a distant fridge compressor several metres away).
Hardware calibration. Every microphone crystal has a small temporal drift (a few parts per million, i.e. a fraction of a second per day) relative to the kernel clock. The Timegrapher calibration in Profile › Calibrate timegrapher measures this drift over 3 minutes of silence and produces a correction factor WatchScope applies to every subsequent reading. Without calibration the rate shows a constant 2–4 s/d offset; with calibration accuracy drops below 0.5 s/d. Recalibrate whenever you change phone or external microphone — the factor is tied to the specific hardware capturing the audio.
External piezo contact microphone. For professional-grade measurements — and especially for vintage watches or quiet calibres (Lemania 1872, Cal. 1861, Peseux 320) — a piezoelectric contact mic placed directly on the case captures the mechanical tick by bypassing the air. The result: tenfold signal-to-noise ratio, stable readings even in noisy rooms, and the option of measuring watches under a closed glass cloche. Connect it via 3.5 mm jack or USB-C adapter, run a fresh Timegrapher calibration (the factor is tied to the hardware) and re-measure.
The grammar of the archive: how to find a watch among thirty, how to track its service history, how to export its precision story.
The Collection tab offers a search bar and a row of quick filters: All, Mint (watches in Mint condition only), Full set (with box and papers) and Watch only (without accessories). Tap the sort icon to switch between most recent, alphabetical, brand and date added. Filters, search and the Favorites segment compose: results narrow down progressively.
Long-press a watch in the collection grid, or tap the star at the top right of the watch detail screen. Favorites get a gold accent in the grid and can be isolated with the Favorites segment — useful for keeping your daily-rotation pieces one tap away.
Open a watch and switch to the Service tab. The + button adds an entry — date, type (full service, partial intervention, water-resistance test, regulation, other), watchmaker, cost and free-text notes.
The most recent full service resets the predictive diagnostics, so post-service health is measured from a clean baseline.
From the Report screen of any watch, tap the gold PDF button at the bottom of the Health tab. The certificate gathers watch info, spec sheet, financial summary (if filled in), the last COSC session, historical trend charts and the predictive diagnostics.
Share it through the system sheet to print it, archive it or send it to a watchmaker.
Cloud, backup, subscription. The foundations everything else rests on: where your data lives, how to recover it, how to manage WatchScope Pro.
WatchScope replicates your collection to Firebase Cloud Firestore (European data centers, ISO 27001), so the same data is available on every device you sign in to. Changes are sent in the background within seconds when you're online; offline writes queue locally and replicate on reconnection.
Watches, measurements and service history are stored under your authenticated account. Reinstalling the app or signing in on a new device restores everything automatically after authentication. There is no manual backup file — the cloud is the source of truth.
WatchScope Pro unlocks unlimited inventory, full COSC tests, microphone calibration, PDF export and predictive-diagnostics charts. Manage your subscription from Profile › Subscription: the customer center lets you switch between monthly and annual billing, restore purchases on a new install, or cancel through the Google Play console.
Every friend you invite gives both of you a free month of Pro, up to 12 free months. You'll find your code and shareable link in Profile › Invite a friend.
Open the app, place your watch next to the microphone and in less than a minute you'll have the first measurement of your collection.