Support

AvGrav is a petroleum API gravity temperature correction calculator, with a Home Screen widget and an Apple Watch app. Reference tool only — not a certified measurement instrument.

Contact

Questions, bugs, or feedback: avclock@protonmail.com
We usually reply within a few days.

FAQ

Why doesn't the corrected result exactly match my physical reference wheel?
AvGrav computes the correction directly from the published API MPMS Chapter 11.1 formula rather than reading it off a printed table, so results should be very close to a correctly-used reference tool. Small differences can still come from rounding, reading precision, or equipment calibration. If a result looks off, treat that as worth double-checking rather than assuming either tool is automatically right — and always confirm against your official procedures.

Does a reading calculated on the Watch show up on my iPhone, or vice versa?
Not currently — the Watch app keeps its own separate history. A reading you calculate on the Watch stays on the Watch; a reading you calculate on the iPhone stays on the iPhone. See the Privacy Policy for details.

Why does the app ask for camera access?
Only if you choose to attach a photo of a hydrometer, gauge, or other physical reading as proof alongside a calculation. It's entirely optional, and the photo is only ever stored on your own device.

How do I get the app on another device?
AvGrav is a one-time paid download, not a subscription. Reinstalling it on any device signed into the same Apple Account you originally purchased with is free through the App Store.

Is AvGrav affiliated with Gammon Technical Products or any other equipment manufacturer?
No. AvGrav implements the publicly published API MPMS Chapter 11.1 correction formula, a public reference standard. It's an independent product, not affiliated with, endorsed by, or sponsored by any standards body or equipment manufacturer.

Privacy
AvGrav collects no personal data and makes no network requests at all. See the Privacy Policy for details.