Chronograde: Watch Accuracy

A pro watch timing machine — right in your pocket. Chronograde reads any mechanical watch's rate and beat error through your iPhone mic, then tracks each watch's daily drift against atomic time. No dock, no $1,000 instrument.

TIMEGRAPHER — LISTEN TO YOUR WATCH
- Rest the phone on the caseback and Chronograde "hears" the balance wheel
- Live rate in seconds per day, plus beat error in milliseconds
- Automatic beat-rate (BPH) lock-on, or set it yourself
- The same spectral-flux signal processing real timegrapher software uses — all on your iPhone or iPad

ATOMIC-TIME ACCURACY TRACKING
- Record a reading when your watch shows a target time — down to the exact second — and Chronograde compares it to NTP-synced atomic time
- Get a signed offset and a rate in seconds per day, charted over days and weeks
- Time synced from public NTP servers (Apple, Google, NTP Pool)
- Works offline using your last sync or device clock (clearly labeled)

ACCURACY BY POSITION
- Tag how the watch was kept for each reading — worn, dial up, crown down, and more
- See how the rate changes with position and the positional variation (the "delta" watchmakers use to judge regulation)
- Combine multiple sessions to see the average rate by position over your watch's life

YOUR COLLECTION
- Unlimited watches with photos, brand, model, reference, serial, caliber
- A per-session drift chart for each watch — start a fresh session after a service or reset
- Sort by rate, last measured, last worn, or recently added
- Color-coded rate: green within ±10 s/day, orange to ±30, red beyond

WEAR & SERVICE
- One tap to log today's wear; days worn in the last 30 or 365 at a glance
- Full service history with provider, cost, and notes
- Set a service interval and Chronograde shows when the next one is due

ATOMIC CLOCK
- Large NTP-corrected clock face for setting your watch, analog and digital

DATA YOU OWN
- Optional iCloud sync across iPhone and iPad via your Apple ID
- Export your full collection to Excel or CSV; import watches from CSV

TRY IT FREE, THEN GO PRO
- Record up to 10 measurements free to try Chronograde
- Chronograde Pro unlocks the Timegrapher, unlimited measurements and sessions, wear & service logs, iCloud sync, and export
- Monthly or annual subscription, each with a 7-day free trial — cancel anytime
- Prefer to pay once? A one-time Lifetime unlock gives you Pro forever — no subscription
- Free users can also earn or buy Crowns for extra measurements and premium themes

Made for watch enthusiasts who care about the seconds.

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Subscription details: Chronograde Pro is offered monthly or annually after a 7-day free trial. Renews automatically until cancelled in Settings > Apple ID > Subscriptions at least 24 hours before the next billing date. Payment is charged to your Apple ID.

Terms: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Privacy: https://mwsupplylimited.github.io/chronograde/privacy.html