Support

Need help or found a wrong result? Contact us in the app: Settings → Feedback. Please include the ticket number if you already sent feedback from the app.

A result looks wrong

Tap “Report issue” on the result card. The calculator, your inputs and the data versions are attached (you can remove them before sending), which lets us reproduce the problem quickly. Confirmed data or formula fixes are published in the changelog (Changelog).

Restore Pro

Go to Settings → SpindleMate Pro → Restore Purchases and sign in with the Apple ID you bought it with. Family Sharing members get Pro automatically when the purchaser has Family Sharing turned on.

Metric and inch

Switch the unit system in Settings or on any calculator. Values are converted at input and output only, so switching never changes the underlying result.

Data updates

Thread, fit, material and cutting start data carry version numbers. Corrections ship with app updates and are listed in the changelog; signed background updates without an app update are planned. Your saved calculations are never changed: if data behind an old record was corrected, the app offers to recalculate it.

Backup and deleting your data

Settings → Backup exports everything as a file; the app also keeps weekly backups visible in the Files app. Settings → Delete all data removes everything from this device.

How calculations work

All formulas and sources are published on the formulas page (Formulas & sources).