Your work stays on your phone

There is no account and no sign-in. Your roofs, dimensions, job names and cut schedules never leave your device unless you share them. CutRoof does send usage statistics, such as which features get used and whether the app crashes, so we can see what to fix and improve. You can turn them off.

What changed, and why

Until 15 September 2026 this page said CutRoof collects nothing, and that was true. From version 1.1 the app sends the usage statistics described below. Without them we cannot see where people get stuck, which features earn their place, or whether the app crashes on phones we do not own. Nothing about your work is included.

What stays on your device

• Saved jobs: the name, address and dimensions you typed, stored on the device in the app's own storage.
• Settings: your conventions, default timber sections and rafter centres.

Deleting the app removes all of it.

Usage statistics

When usage statistics are on, the app sends:

• Which features you use: setup, the roof types you start, whether a roof worked out or showed an input error (the kind of error, never the figures), Working, the conventions you change, reference articles, saving, opening and deleting jobs, exporting, printing and sharing schedules, and opening Send feedback (that it was opened, never what you write). For a shared schedule it records the kind of app it went to, such as Mail or WhatsApp.
• Screens and fields (from version 1.3): which screen or step you are on, and which fields you tap into and how many you change, never what you type.
• Roofs you work out (from version 1.3): whether you have worked out a roof of your own, and a grouped count of the roofs you save, duplicate or open as a cut schedule (1, 2, 3, 4 to 5, or 6 or more).
• Setup: whether you finished, skipped or closed it (closed is recorded from version 1.3), and, if you finished it, the defaults you chose there: ridge allowance, hip treatment, which built-in rafter-section size you chose (or just "custom" for a size you added), and rafter centres.
• The unlock: when the unlock card or screen is shown, and whether a purchase was started and then completed, cancelled, left waiting for approval or failed. A completed purchase includes its price and currency.
• Opening, closing and crashes: when the app is opened and put away, and the technical details of any crash.
• Repeated taps on one spot: where on the screen and which screen, which usually means something looks tappable and is not.
• About the phone and app: phone model, screen size, iOS version, app version and build, language, time zone, whether you are on Wi-Fi or mobile data, your App Store country and the region your phone is set to.
• A random ID the app creates for this install, so that a return visit is not counted as someone new. It is not linked to your name, email, Apple Account or any other app, and deleting the app deletes it.

It never sends any dimensions you type, including custom timber sizes; roofs, cut schedules or PDFs; job names, addresses or anything else you type; or your name, email, contacts, photos or location.

Taps on selected buttons (from version 1.2): the app counts taps on a chosen set of buttons, such as Next in setup or Share on a schedule. Each button is identified by a fixed internal name, never by the text shown on it or anything you enter. The same usage-statistics setting controls this collection. Versions up to 1.1 did not count button taps.

Your IP address reaches our analytics provider when statistics are uploaded, because that is how the internet works. It is not stored, and it is not used to work out where you are.

How the statistics are used

Only to understand and improve CutRoof: how many people finish setup, which features get used, where people stop, whether the free roof and the unlock make sense, how many come back, and what crashes. We look at them in aggregate, not at what any one person did.

They are not used for advertising, not sold, not shared with advertisers or data brokers, and not combined with information from anywhere else. CutRoof does not track you across other companies' apps or websites.

Who processes them

PostHog, our analytics provider, handles the statistics for us, on our instructions, on servers in the EU. Event records are kept for up to seven years, the retention period of our PostHog plan.

Your choices

Usage statistics are on by default when you first open the app in every country, including the European Economic Area, Canada and mainland China, and setup says so. Turn them off in Settings › Usage statistics, and collection stops straight away. If you have already turned them off, they stay off. You can change the setting at any time.

Because the statistics are not linked to your name, email or Apple Account, we cannot pick out the ones from your phone, so we cannot act on a request to see or delete them. Turning statistics off stops any more being sent, and deleting the app deletes the ID they were sent with. You can complain to the Information Commissioner's Office or to the data protection authority where you live.

The legal basis

We rely on our legitimate interests in understanding how CutRoof is used so we can fix and improve it (Article 6(1)(f) of the UK GDPR and the EU GDPR). The statistics are on by default for everyone; you are told about them here and in the app, and you can object free of charge at any time with the setting described above.

Cut schedules you share

When you export a schedule as a PDF, iOS hands the file to whatever you pick: Mail, Messages, AirDrop, a printer, Files. That is your choice and your data, and it happens through Apple's own share sheet. CutRoof does not upload it and does not keep a copy beyond the job you saved.

What Apple sees

The app is free to download. If you buy the one-off unlock inside it, Apple processes that purchase and Apple's terms cover it rather than ours. We never see your payment details, and Apple does not tell us who bought it. With usage statistics on, the app records that a purchase completed and its price, against the random install ID rather than against you.

Apple also provides aggregate App Analytics to developers: figures such as how many people installed the app or how often it crashed. These are collected by Apple, are aggregated across everyone, and can be switched off in Settings › Privacy & Security › Analytics & Improvements on your iPhone.

Ad attribution

CutRoof uses Apple's built-in ad attribution (SKAdNetwork and AdAttributionKit). When someone installs the app after seeing a CutRoof ad, Apple can tell the ad network that an install happened and whether the unlock was bought. Apple sends this as aggregated, delayed reports without any identifier for you or your device. CutRoof does not use advertising identifiers, does not track you across other companies' apps or websites, and shows no tracking permission request. Apple also sends a copy of these aggregated reports to AppsFlyer, which turns them into campaign results for us; the app itself sends AppsFlyer nothing and contains none of its code. This does not depend on the usage statistics switch, because no information about you is collected.

Third-party code

The app includes one third-party component: PostHog's open-source iOS SDK, which sends the usage statistics described above. Session recording and surveys are switched off. From version 1.2 it also counts taps on selected buttons, by fixed internal name only, as described above; versions up to 1.1 did not. Text you enter is never collected. The geometry, the drawings and the cut schedule are all the app's own code.

Children

CutRoof is a tool for carpenters. It is not directed at children, and we do not knowingly collect anything from them.

Changes

If what CutRoof collects changes again, this page changes before the app does, and the change will say plainly what moved and why.

Who we are

CutRoof is made in the UK by We Evolve, which is responsible for the usage statistics. Questions about any of this go to support.