Privacy Policy

English Coach — AI Speaking Tutor · Last updated 19 August 2026

In short: nothing leaves your device unless you choose to publish a certificate. English Coach runs its speech recognition and AI tutoring entirely on your iPhone, iPad or Mac. Your voice, your writing and your learning history stay on your device, and we have no way to read them. The single exception is deliberate: if you decide to publish a certificate for public verification, the details you approve are sent to us and shown on a public page.

Who we are

English Coach is published by Stacklab X Limited, the data controller for the purposes of the UK GDPR and the Data Protection Act 2018. If you have any question about privacy, write to support@stacklabx.com. Full company details, our lawful bases and your rights are set out in the full privacy notice.

What we collect

Nothing automatically. The app has no accounts, no sign-up and no user profiles on our side. We do not use third-party analytics, advertising SDKs or trackers, we do not build advertising profiles, and we never sell or share your data.

We receive personal data in one situation only: when you choose to publish a certificate, described next.

Publishing a certificate

Certificates are issued and stored on your device. Publishing one is optional, off by default, and asked for per certificate. If you publish, we receive the certificate ID, the name label you choose (initials or your full name), the level and skill levels, the issue date and the version stamps of the scoring rules. Nothing else — no recordings, no transcripts, no practice history.

The result is a public page at ecouch.stacklabx.com that anyone with the link can read and search engines can index. Our lawful basis is your consent, which you can withdraw at any time: email us with the certificate ID and we will remove the page. The certificate itself stays valid on your device either way. Published data is stored on servers in the United Kingdom.

Your rights

You have the right to access, correct, erase, restrict, object to and port any personal data we hold, and to withdraw consent. Since we hold nothing unless you published a certificate, most requests are handled by removing that page. Write to support@stacklabx.com and we will respond within one month. You can also complain to the Information Commissioner's Office at ico.org.uk.

Your microphone

The app asks for microphone access so you can practise speaking. Audio is processed on your device by Apple's on-device speech recognition to produce a transcript. Recordings are not uploaded anywhere and are not retained after the words have been recognised. Only the transcript and derived measurements — such as word counts and speaking pace — are kept, and only on your device.

Artificial intelligence

Conversations, corrections, writing feedback and estimated levels are produced by Apple's Foundation Models framework running on your device. Your words are not sent to us or to any AI provider over the internet. On devices that do not support on-device AI, the app tells you plainly and offers guided practice instead.

What is stored on your device

Your learning profile: goal, level estimates and daily target
Session history, transcripts of your practice, corrections and scores
Saved vocabulary, review schedules and lesson progress
Any certificates you have earned

This data lives in the app's private storage, protected by iOS file encryption. Deleting the app removes it.

Your control over your data

Export — Profile → “Export my data” produces a JSON file containing everything the app holds about you.
Delete — Profile → “Delete all my data” erases your profile, history, saved words, certificates and evidence from the device. This cannot be undone.

When the app does use the internet

English Coach makes no network requests of its own. Two Apple services may use the network on your behalf:

Speech models — iOS may download British English speech-recognition assets the first time you use voice practice. This is handled by Apple; we receive nothing.
Subscriptions — purchases, restores and renewals are handled entirely by Apple through the App Store. We never see your payment details. Apple's privacy policy governs that processing.

Notifications

If you allow notifications, practice reminders are scheduled locally on your device. There is no push server, and no notification data leaves your device.

Certificates

Certificates you earn are generated and stored on your device. They are issued by StackLabX based on your work in the app and are not IELTS, TOEFL, Cambridge, government or university qualifications. If online certificate verification is introduced in a future version, it will be optional, you will be asked before anything is uploaded, and this policy will be updated first.

Children

English Coach is a general-audience app and is not directed at children under 13. Because we collect no personal data at all, we do not knowingly collect personal information from children.

Changes to this policy

If the app's data practices ever change — for example if a feature needs a server — we will update this page and the App Store privacy details before that version is released.

Contact

Questions, requests or complaints: support@stacklabx.com.