Lozenge is a trainer for the Cambridge B1 Preliminary, B2 First and C1 Advanced exams, for iPhone, iPad and Android. This page explains what the app does with your data, and how to get help.
Last updated 3 October 2026 · applies to Lozenge 2.0 and later
Most of Lozenge stays on your phone: your lessons, your progress, your Speaking recordings and your drafts are not uploaded anywhere.
Data leaves your phone only when you choose it: if you create an account (so your progress follows you to another device), if you ask the AI examiner to mark a piece of Writing or a Speaking answer (the app asks you first), or if you choose to watch a short video for extra gems or energy. If the app crashes, a short technical crash report is sent so we can fix it – it never contains your name, your account or anything you wrote.
Everything you do in Lozenge is saved locally: your answers, XP, streak, energy, saved words, essay drafts, the feedback you receive, your daily goal, the exam you are preparing for, your exam date and your settings. Deleting the app deletes all of it.
If you add Lozenge widgets, a small summary (streak, today's XP, the word of the day) is stored on your device so the widgets can read it. It never leaves your device.
An account is optional. Lozenge works completely without one.
| Data | Why | Kept |
|---|---|---|
| Email address | To sign you in and let you reset your password. If you sign in with Apple or Google, we receive the email address they share with us (with Apple this can be a private relay address). | Until you delete your account |
| Display name | Shown on the weekly league board | Until you delete your account |
| Progress summary (XP, streak, lesson results) | To sync your progress between your devices and rank the weekly league | Until you delete your account |
| Invite code | If you invite friends or use a friend's code, to give both of you the free week of Plus | Until you delete your account |
| Number of AI markings per day | To apply the daily limit of the AI examiner. Only the count is stored – never your text. | Until you delete your account |
Accounts are hosted on Supabase, which stores this data on our behalf. We do not sell data, we do not share it with advertisers, and we do not use it to build profiles.
In the app: Profile › Settings › Account › Delete account. This removes your email, your name and your synced progress from the server immediately. You can also email us and we will do it for you within 30 days.
When you have an account and tap Mark, Lozenge can have your answer marked by an AI examiner. The first time, the app tells you what is sent and asks for your permission; you can switch the AI examiner off at any time in Settings › AI examiner.
If you do not want this, leave the AI examiner off: Writing is then marked on your phone – with Apple's on-device model on supported iPhones, or with a simple offline estimate – and nothing is sent.
If you start a conversation with the live examiner, your voice is streamed over an encrypted connection to ElevenLabs, which turns it into text and answers with the examiner's voice in real time. To decide what the examiner says next, ElevenLabs uses an AI model made by Google (Gemini). The audio is not recorded or kept. The text of the conversation is kept by ElevenLabs for up to 30 days, and your half of it is sent to Claude (see above) to mark your speaking. Before your first conversation the app explains this and asks you; nothing is sent unless you agree and press Start, and you can withdraw the permission in Settings › Live examiner.
If you join a teacher's class with its code, the teacher sees your name, XP, streak, this week's XP, when you last practised and the scale scores of your mock tests. They never see your answers, essays, recordings or anything else from your progress. The app tells you this before you join, and you can leave a class at any time in Settings › Classes; deleting your account removes you from every class. A teacher who deletes a class deletes its list of students.
When the app crashes or a screen fails to load, a technical report is sent to Sentry, which stores it for us in the EU (Germany). It contains what went wrong (the error and where in the code it happened), which screen you were on, the app version, your device model and system version. It does not contain your name, email, account, answers or anything you wrote, and it is used only to fix bugs – never for advertising or tracking. Reports are deleted after 30 days.
Your recorded answers are stored on your phone, turned into text on the phone and measured there (pace, pauses, range of grammar and vocabulary, how clearly you were understood). The audio never leaves your device, and you can delete all recordings in Settings › Speaking recordings.
Lozenge has exactly one ad placement: a short rewarded video you can choose to watch – from the energy screen or Settings – in exchange for gems and, when your energy is low, a little extra. You are never shown a video without asking for one, and nothing else in the app carries advertising.
These videos are served by Google AdMob. Depending on your region and your choice, Google may use identifiers on your device to show a more relevant video; if you decline, or your region requires asking first, you still get the same video and the same reward, just untargeted. You can see and change this choice at any time in Settings › Ad privacy (shown where it applies), and on iPhone in the "Allow Tracking" prompt iOS shows the first time you open the app.
See how Google uses information from apps that use its services for what Google itself collects when it serves one of these videos.
Lozenge Plus is sold through Apple's In-App Purchase on iPhone and iPad, and through Google Play Billing on Android. Apple or Google processes the payment; the app only learns whether your subscription is active. We never see your card, your address or your store account details. Manage or cancel a subscription in Settings › Apple Account › Subscriptions on iPhone, or in the Play Store under Payments & subscriptions on Android.
Lozenge is suitable for all ages and contains no objectionable material, but it is designed for exam candidates. We do not knowingly collect data from children under 13. If a child has created an account, email us and we will delete it.
Practice reminders are scheduled locally on your device only if you turn them on. No push server is involved.
You can ask for a copy of the data linked to your account, ask us to correct it, or ask us to delete it. Write to the address below and we will answer within 30 days. If you are in the EU and are not happy with our answer, you can complain to your national data protection authority.
Questions, bug reports, a sentence you think is wrong, or a feature you would like:
Email: skalivoda70@gmail.com
Please include your phone model and the app version (Profile › Settings, at the bottom). We usually answer within a few days.
If this policy changes, the date at the top changes with it, and significant changes are announced in the app.