Privacy policy

Last updated 1 September 2026.

The short version

The app analyses your practice on your phone. Your recordings and your history never leave it.
We do not collect personal data through the app. There is no account, no analytics and no advertising.
This website adds no trackers and sets no cookies. Our host sees the ordinary details any web server sees to deliver a page.
Free. There are no payments, no subscriptions and no advertising.
Questions or requests, wherever you live: hello@skillmirror.net.

Who operates SkillMirror

SkillMirror is a trading name used by an individual based in the United Kingdom. It is not a registered company.

For everything in this policy, whether a question, a request about your data or a complaint, write to hello@skillmirror.net. That address is read by the person who runs the product.

This policy covers the SkillMirror phone app and the website at skillmirror.net. It applies to everyone who uses them, wherever in the world they are.

The app: your practice stays on your phone

Each statement below is true of the app as it is built today, with a note under it saying how you can tell.

Analysis runs entirely on your phone. Recordings are processed on the device that made them.
You can prove this to yourself: put the phone in aeroplane mode and practise as normal. Everything still works, because there is nowhere for a recording to go.
Nothing you record is uploaded. The app has no way to upload at all.
Not a setting you have to find and switch off. There is no upload in the app to switch off.
When you choose an existing video, the app is given only that one file. It never asks for access to your photos and never looks through your library.
Your phone chooses the file, not the app. That is why the app never asks for photo-library permission, and why your phone will never show you a request for one.
A video you choose stays where it is on your device. The app reads its length and size, opens it once to check it can be played, and analyses it there.
No copy is made to send anywhere, because nothing is sent anywhere.
Your practice history is stored only on your phone, and deleting the app deletes it.
There is no copy of it anywhere else, so there is nothing to ask us to delete. The app also tells you the limit on how much history it keeps, on the screen where the history appears.
You can export an encrypted backup protected by a passphrase you choose. It holds your practice records, not your recordings, and only you hold the passphrase.
If you lose the passphrase, the file cannot be opened by anyone, including us. That is the point of it, and it means you should keep the passphrase somewhere safe.
The microphone is recorded together with the video, because that is how a phone records. Movement analysis does not use the sound.
A voice-practice feature is built but switched off in the app you can install. If it is ever switched on, it will listen on the phone the same way the movement analysis watches on the phone, and this page will say so before that version reaches you.
The app creates no account, sets no advertising identifier, and contains no analytics or tracking of any kind.
There is nothing to sign up for and nothing to opt out of. The declaration the app makes to Apple and Google says the same: no tracking, no data collected.
The app measures how your body moves, as angles at your joints over time, and compares that with the reference. It does not identify you, recognise faces, or infer emotions, and nothing it measures leaves the phone.
What it works from is a stick figure: a set of points for shoulders, elbows, hips, knees and so on. Your face is not one of the things it measures.

What leaves your phone

Nothing, from the app. While you are practising, the app never contacts the internet. The only way a practice record leaves the phone is an encrypted backup file you choose to export, protected by a passphrase only you hold, and you decide where that file goes. Your phone’s operating system may collect its own diagnostics for Apple or Google under your device settings; that is theirs, not ours, and we receive none of it.

This website

The public pages add no analytics, no advertising and no third-party trackers, and set no cookies. There is no cookie banner because there is nothing to consent to.
Open your browser’s privacy or storage panel on any page of this site and you will find it empty.
The website is served by Vercel. Like any web host, Vercel receives your IP address and standard request details in order to deliver the pages and protect the site from abuse.
That is the same information any website you visit receives. We add nothing to it, and we do not read or keep those records ourselves.
The practice tools on this site read the files you choose inside your own browser and never upload them.
The same test as the app: disconnect from the internet once the page has loaded, and the practice tools keep working on your video.
This website offers no accounts. There is nothing to sign up for and no password to lose.
An optional account is built but switched off here. If it is ever switched on, it would store the email address you signed up with and keep you signed in with a cookie, and this page would say so before that happened.
If you email us, we keep your message for as long as it takes to answer it and deal with what you asked, and no longer.
It goes to one address, read by the person who runs the product. There is no help-desk system behind it and no mailing list.

What we do not do

We do not sell personal data, and we do not share it for advertising.
We do not profile you or make automated decisions about you.
We do not use your recordings, or anything derived from them, to train models. We could not: they never reach us.
We do not show advertising anywhere in the product.

The legal basis for the little we process

Under the UK GDPR and the EU GDPR, the only personal data we process is the request information our web host handles to serve this site and keep it secure, and any email you send us. Our basis for both is legitimate interests: running a website safely, and answering the people who write to us. The app processes no personal data on our behalf at all. It processes your practice on your phone, for you.

Your rights in the UK and the European Union

If you are in the United Kingdom or the European Economic Area, the UK GDPR or the EU GDPR gives you the right to ask us for access to your personal data, to have it corrected or erased, to restrict or object to its processing, to receive it in a portable form, and to withdraw any consent you gave. Because the app keeps everything on your phone, access, export and deletion of your practice data are already in your hands: the history is visible in the app, the encrypted backup is your export, and deleting the app deletes the data.

To exercise any right, email hello@skillmirror.net. We answer within one month. You also have the right to complain to a supervisory authority: in the UK that is the Information Commissioner’s Office (ico.org.uk); in the EU it is the authority for the country you live in.

Your rights in California

If you live in California, the CCPA as amended by the CPRA gives you the right to know what personal information we collect and how we use it, to delete it, to correct it, to opt out of its sale or sharing, to limit the use of sensitive personal information, and not to be discriminated against for exercising those rights.

Categories collected in the last twelve months: through the website only, identifiers (your IP address) and internet activity (the pages requested), received by our host in order to serve the site. Through the app: none.
We do not sell personal information and we do not share it for cross-context behavioural advertising, so there is nothing to opt out of. We collect no sensitive personal information.
To make a request, or to have an authorised agent make one for you, email hello@skillmirror.net. We will confirm it is you before acting on a request about your data, and we respond within forty-five days.

Everywhere else

The same standard applies wherever you live. Whatever the privacy law of your country calls them, in Brazil, Canada, Australia, India, Japan or anywhere else, you can ask us the same things: what we hold, to correct it, to delete it, and to stop. Email hello@skillmirror.net and we will deal with your request under the law that protects you.

Children

The app collects no personal data from anyone, including children, so there is nothing for a parent or guardian to consent to under the United States COPPA rules, the UK and EU age-of-consent provisions, or their equivalents elsewhere. This website is not directed at children under 13. If the website ever offers accounts, they will be for people aged 16 or over. If you believe a child has sent us personal data, email hello@skillmirror.net and we will delete it.

Where data is handled

The operator is based in the United Kingdom. The website is served by Vercel, whose servers may handle request details outside the UK and the European Economic Area, including in the United States, under Vercel’s standard data-processing terms and the standard contractual clauses those terms include. Your practice data is never transferred anywhere, because it never leaves your phone.

How long anything is kept

Practice data: on your phone, for as long as you keep it. Web request details: held by our host for its short standard period. Emails: for as long as it takes to deal with what you asked, then deleted.

Security

Practice data on your phone is protected by the phone’s own security. Backups you export are encrypted with a passphrase only you know; if you lose it, nobody, including us, can open the file. The website serves everything over a secure connection.

When this page changes

If a future version of the app ever sends anything off your device, this page will say so before that version reaches you, not after. The date at the top is the date of the last revision.

About this page

Written in plain language by the people who built the product. A review by a qualified lawyer is planned before the app is submitted to the app stores, and this page will be updated if that review changes anything.