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Yes. Feet, inches and sixteenths (or thirty-seconds), millimetres or centimetres, and pitch in 12ths, degrees or percent. The app starts with your region's units and you can change them in Settings at any time.

Stair rules from 10 countries: the IRC and IBC in the US, NBC 2020 in Canada, Approved Document K in England, DIN 18065 in Germany, the French arrêtés, the Dutch Bbl, the Spanish CTE, the Italian DM 236/1989, the Australian NCC and the Turkish PAİY. Each rule shows its clause and edition. Rules taken from secondary sources are labelled. A stair is shown "within limits", never "approved": check the current rules with your local building authority.

Free for good: straight stairs with every number, your country's code check, headroom, what would make it fit, the common rafter with the birdsmouth check, the pitch gauge, stringer numbers, the job card, unlimited jobs and backups. Pro is one payment: landings, L and U stairs, winders and spirals, a second code side by side, the inspector sheet as a PDF, the marked stringer drawing, and hips, valleys and jacks.

Tap "Try Pro free for 7 days" on the Pro screen. No card is asked and nothing renews. After 7 days Pro stops unless you buy it. Every job you made stays readable, editable and exportable.

Open Settings and tap "Restore purchases" with the same store account. Pro comes back on every phone you own.

In Settings, Back up shares one file through the share sheet: save it to Files, Drive or mail it to yourself. On the new phone, Restore a backup and pick the file.

Lay the phone's long edge on the rafter, take a reading, turn the phone end for end on the same spot and take a second one. The two readings are averaged, which cancels the phone's own tilt. A bent case or a warped board shows up as a difference between the two readings. If in doubt, measure the rise over a level 12 in.

Every result has its formula under it with your numbers; tap it to see the working. If it still looks wrong, write to hello@mufatech.com with the job (a backup or a job card helps). We answer every message and fix confirmed errors first.