Privacy
What this covers
This notice covers the Lumessa app on iPhone and Android, and this website, getlumessa.com. It replaces the website-only notice published on 13 August 2026.
Who we are
Lumessa Limited, a company registered in England and Wales, company number 17335480, registered office 71–75 Shelton Street, Covent Garden, London WC2H 9JQ, United Kingdom. We are the controller of the personal data described below.
Write to hello@getlumessa.com, or telephone 020 3355 8301.
We are registered with the Information Commissioner's Office under reference ZC219318.
The short version
You can use the whole free tier of the app without telling us who you are. The words you learn, your review schedule, your streak, your settings and any name you type at the start all live on your phone, and none of it is sent to us unless you choose to create an account.
Five things do leave the phone, and each has its own section below: the audio files the app downloads; an account, if you make one; a subscription, if you buy one; the usage notes, only if you say yes to them; and a crash report, if the app crashes.
We do not sell personal data, we do not share it for advertising, and there is no advertising in the app. The app never asks your phone for its advertising identifier.
Using the app without an account
The word banks, the example sentences, the memory hooks and the grammar notes are inside the app. What you learn is recorded on your device: which words you have met, when each is next due, how you answered, what you favourited, and any note you write under a word. The first name you may give during onboarding is kept on the device and nowhere else.
Audio: the pronunciation recordings are too large to ship inside the app, so the app downloads them as you need them and keeps them on the device. They are served by Cloudflare, which records the technical details of each request: the internet (IP) address it came from, the time and the file requested. That is the same record our website host keeps, described below, and it is held for the same short period.
Reminders and the widget: the daily reminder and the lock-screen widget are scheduled and drawn on your device. Nothing about them is sent to us.
If you create an account
An account is optional. It exists to back up your learning and to keep it in step across your devices.
What we hold: your email address; the sign-in identity you used, which is Sign in with Apple, Google, or an email address with a password (the password is held only in a hashed form we cannot read); if you signed in with Google, the name Google sends with the sign-in; and a copy of your learning progress and settings, which is the same record the app keeps on your phone: the words you have met, when each is due, your quiz answers and how long each took, your favourites, the notes you write under words, your chosen language and pace, your reminder setting and time, and your answers to the onboarding questions about why and when you learn.
Why: to keep your learning safe if you lose or change your phone, and to let you continue on another device.
Our lawful basis: the account is a service you asked for, so we process this data to provide it.
How long: for as long as the account exists. Deleting the account, from Settings → Account inside the app or by writing to us, removes the account and every record held against it at once: the account itself, your learning record and settings, your answer about emails from us and the record of it, any trial-reminder record, the usage-notes profile filed under your account, and the link between you and the subscription record described below. We hold no backup copies of the account database, so there is no copy for a deleted account to linger in. There is a page for that written for someone who no longer has the app: deleting your account and your data.
Who processes it: Supabase (Supabase, Inc.), which stores the account and the backup on our instructions. Our Supabase project is hosted in Frankfurt, in the European Union, and Supabase encrypts all customer data at rest and in transit.
If you subscribe to Lumessa Pro
Payment is taken by Apple or Google, through their store. We never see your card or bank details, and your relationship for the payment itself is with the store, under its own terms and privacy notice.
What we hold: a record that a subscription exists: an identifier the store assigns, which product it is, when it started and renews, and whether it is set to renew. If you are signed in, the record is filed against your account so that Pro follows you to another device. If you are not signed in, it is filed against an anonymous identifier held on your phone.
Why: to unlock Pro on your devices, to restore it after a reinstall, and to send the one reminder described next.
Our lawful basis: the subscription is a contract, and this is what performing it needs.
The trial reminder: the annual plan begins with a free trial, and we promised at the start that you would be reminded before it ends. The reminder is a notification on your phone, scheduled on the device. If you are signed in, we also send one email, two days before the trial ends, from hello@getlumessa.com. To send it we hold your email address and the date until the email has gone or the trial has been cancelled, and then the record is deleted.
How long: the subscription record is kept while the subscription exists and for as long as we need it to answer a question about a payment, and deleting your account asks RevenueCat to delete the record it holds under your account. The store's own record of your purchase stays with Apple or Google under their terms. Resend keeps a record of each email it has sent, including its content, for 30 days.
Who processes it: RevenueCat (RevenueCat, Inc., United States), which keeps the subscription record and tells the app whether Pro is active; and Resend (Resend, Inc., United States), which sends the trial-reminder email on our instructions.
Usage notes
During onboarding the app asks one question: whether it may keep private notes on how it is used. The notes are off unless you say yes, and saying no changes nothing about the app.
What they are: a record of events inside the app, such as a word being revealed, a quiz question answered, a screen opened or a subscription started, each with the time, the type of phone, its operating system version and the app version. Alongside the events we keep a small profile: your language, your pace, your streak length, the number of words learned, your answers to the two onboarding questions, and whether the widget is installed. The notes are tied to a random identifier the app creates. If you sign in, they are tied to your account identifier instead, so that your history stays in one place. They are never tied to your name or to anything you type: no note, no search, no answer you write is ever sent.
What we deliberately do not collect: your IP address, which is stripped before the note is stored; your location; and your phone's advertising identifier, which the app never reads.
Why: to see which words prove stubborn, where sessions pause, and whether the daily ritual is working, so that we can improve it.
Our lawful basis: your consent. You can withdraw it at any time in Settings → Privacy → Usage notes. Withdrawing stops the notes at once and destroys the identifier on your phone, so anything recorded before cannot be connected to anything after.
How long: each note is deleted two years after it was recorded. When you withdraw consent, the app also asks Mixpanel to delete the profile held under your identifier.
Who processes it: Mixpanel (Mixpanel, Inc.), which stores and analyses the notes on our instructions. Our Mixpanel project is held in the European Union.
If the app crashes
When the app crashes, it sends us a report so that we can fix the fault. The report holds the technical trace of what went wrong, the app version, the operating system version, the model of phone, and the names of the last few screens and controls the app passed through before it stopped. It does not hold your name, your email address, your location, or anything you typed, and your IP address is not stored with it.
Our lawful basis: our legitimate interest in keeping the app working. A report is only ever sent when the app has actually crashed.
How long: ninety days.
Who processes it: Sentry (Functional Software, Inc.), which receives and stores the reports on our instructions. Our Sentry project is held in Germany, in the European Union.
If you gave us your email address on this website
What we hold: the email address you give us, the date and time recorded against it, and the internet (IP) address your browser was using. The time and that address together are the record that consent was given.
Why: to send you one email about Lumessa's release, and after that a short note when a new language, article or feature arrives, a few times a year at most. The sign-up form was taken off this website on 8 October 2026, so no new addresses are added through it. If you signed up when the form promised a single message on the day Lumessa is released, that single message is the only one we will send you.
Our lawful basis: your consent. You give it by entering the address and then following the link in the confirmation email we send. Until you follow that link the address is not used for anything, and if you never follow it, nothing is ever sent to it.
How long: until you unsubscribe, or until we close the list, whichever comes first. If a year passes with nothing sent, we will write once to say so and close the list.
Who processes it: MailerLite (UAB MailerLite, Lithuania), which stores the list and sends the messages on our instructions. MailerLite is established in the European Union, and uses its own suppliers to run the service it provides to us.
Opens and clicks: MailerLite records whether the emails it sends for us are opened and whether their links are clicked. For the confirmation email, this cannot be switched off on the plan we use. Unsubscribing works on the first click, without a login and without a preference page.
If you ask us to email you about Lumessa
The app has a switch, off unless you turn it on, that lets us write to your account's email address about Lumessa Pro and new features. It is offered when you sign in or create an account, and it is under Settings → Privacy → Emails about Lumessa. As at the date at the top of this notice, no such email has yet been sent to anyone.
What we hold: your answer, the time you gave it, and the address it applies to, kept with your account. Each time the switch is turned on or off, a further line is recorded, so that we can show what you chose and when.
Why: to tell you, now and then, about Lumessa Pro and about new features.
Our lawful basis: your consent. Nothing is sent unless the switch is on, and turning it on is not a condition of anything else in the app.
How long: until you turn the switch off, unsubscribe, or delete the account. Turning it off stops further emails at once. The record that you turned it on and then off stays with the account, so that we can show we stopped when you asked, and it is deleted with the account.
Who processes it: Resend (Resend, Inc., United States), which would send these emails on our instructions, as it sends the trial reminder described above, and which keeps a record of each email it has sent, including its content, for 30 days.
What we do not do: we do not send anything to an address whose switch is off, and every email carries an unsubscribe link that works on the first click, without a login and without a preference page.
When you visit this site
The site is hosted by Cloudflare, which records the technical details of each request: the IP address it came from, the time, the page requested, and the browser and operating system reported. An IP address is personal data, which is why this section exists. The site sets no cookies, stores nothing on your device unless you ask it to stop counting your visits, and makes no request to any third party: everything your browser loads comes from getlumessa.com.
Why: to keep the site available and to defend it against attack and abuse.
Our lawful basis: our legitimate interests in the security and availability of our own website. The records are technical, are not linked to anything else, are not used to build any picture of you, and are not read at all unless something goes wrong.
How long: these records sit with Cloudflare and are deleted after a short period that Cloudflare sets rather than we do. We keep no copy of our own.
How we count visits to this site
A small script of ours counts visits, so that we can see which pages and articles people read and whether the site is doing its job. It sends a short note to our own server at getlumessa.com, and our server passes it on to Mixpanel. Your browser never contacts Mixpanel.
What is counted: the page you opened; whether you came from another page of this site or from somewhere else, and if from somewhere else, the name of the site that linked here but never its full address; any campaign tag in the link you followed; whether you are on a phone, a tablet or a computer; how long the page was in front of you, and whether that reached ten seconds; on the home page, which of its sections stayed on your screen for a second; on an article, how far through it you scrolled and how long it had been in front of you by then; which questions you open in the questions section; when you follow a link to email or telephone us, to an app store, or to another website, and for another website its name only; and, if you land on a page that does not exist, the address you tried, without anything after a question mark. When you follow one of our short links (such as getlumessa.com/ig) on the way to an app store, it also counts which link it was and which store it sent you to. Our server adds the country your connection comes from, which Cloudflare tells it, and the operating system your browser reports.
How visits are told apart: our server makes a code from your IP address and your browser's description of itself, mixed with a secret key and the date. Every page you open on the same day gets the same code, so we can see that one visitor read three pages rather than three visitors reading one. The next day the code is different, so visits on different days cannot be connected, and the code cannot be turned back into your address. Your IP address itself is not stored and is not passed to Mixpanel.
What we do not do: the counting itself sets no cookie, stores nothing on your device and reads no identifier from it. It is not linked to your email address, to an account, or to the app's usage notes, which are kept separately. It is never used for advertising and is not shared for anyone else's purposes.
Our lawful basis: our legitimate interest in understanding how our own website is used, so that we can improve it.
Turning it off: if your browser sends a Global Privacy Control or Do Not Track signal, nothing is counted. You can also turn the counting off here. The choice is kept in this browser, and it is the only thing this site stores on your device. One exception: a short link sends you straight to the store without showing you a page, so it cannot see the choice kept in your browser. It does respect a Global Privacy Control or Do Not Track signal.
How long: each count is deleted two years after it was recorded.
Who processes it: Mixpanel (Mixpanel, Inc.), which stores and analyses the counts on our instructions, in a project held in the European Union and kept apart from the app's; and Cloudflare, which runs our server.
If you write to us
We hold your address and what you wrote, for as long as it takes to deal with it and for 24 months afterwards.
Our lawful basis: our legitimate interest in answering people who write to us.
How it reaches us: mail addressed to hello@getlumessa.com is forwarded to our mailbox by Cloudflare Email Routing. Cloudflare states that it does not store or read the contents of the mail it forwards; it checks for phishing and passes the message on.
Where it is then held: our mailbox is Gmail, provided to us by Google LLC in the United States, which stores and delivers the message.
If you telephone us
The number on this site rings to voicemail, and the greeting asks you to write to us instead. If you do leave a message, we hold the recording, the number you called from and the time of the call, for as long as it takes to deal with what you called about and for 24 months afterwards.
Our lawful basis: our legitimate interest in answering people who contact us.
Who processes it: Yay.com (YayYay Limited, a company registered in England and Wales, company number 08738610), which takes the message and holds it until we delete it.
Sharing
We do not sell personal data and we do not share it for advertising. The organisations that handle it on our instructions are named in the sections above: Supabase, RevenueCat, Resend, Mixpanel, Sentry, Cloudflare, MailerLite, Google and Yay.com, together with the suppliers each of them uses to run its own service. Each of them is bound by a written contract with us to use the data only on our instructions and to protect it to at least the standard described in this notice. Apple and Google handle your purchase under their own terms, as the store you bought from. We would also disclose data where the law required us to.
Where your data is held
Your account and backup (Supabase), the usage notes and the counts of visits to this site (Mixpanel), crash reports (Sentry) and the email list from this website (MailerLite) are all held in the European Union.
The subscription record (RevenueCat) and the trial-reminder email (Resend) are handled in the United States, and mail sent to us is held there by Google. Cloudflare operates a global network, so technical records of requests to this site and to the audio files may be processed outside the United Kingdom. For each of these transfers we rely on the provider's contract with us, which includes the terms the UK requires for a transfer abroad, or on the provider's certification under the UK Extension to the EU–US Data Privacy Framework where it holds one.
Keeping it safe
Everything the app sends travels over an encrypted connection, and so does everything this site does, and each of the services named above holds what it stores for us encrypted at rest. Passwords are held only in a hashed form. Access to the account records, the usage notes and the mailbox is limited to the people at Lumessa Limited who need it, which at present is one person, on accounts protected by two-step verification.
Your rights, and how to use them
You can ask us to give you a copy of the personal data we hold about you, to correct it, to delete it, to restrict what we do with it, or to give it to you in a portable form. You can object to processing we carry out on the basis of our legitimate interests. Where we rely on your consent, you can withdraw it at any time: for the usage notes, the switch in Settings → Privacy does exactly that; for emails about Lumessa, the switch in Settings → Privacy or the unsubscribe link in any email; for the email list from this website, unsubscribing does.
You can delete your account and everything held against it yourself, from Settings → Account inside the app. For any other request, or if you no longer have the app, write to hello@getlumessa.com. You do not need to use any particular words. It costs nothing, and we will respond within one month of receiving your request, which is the period the law gives us.
Deletion has its own page, written for someone who no longer has the app or the device: deleting your account and your data.
Complaints
If you are unhappy with how we have handled your personal data, tell us first at hello@getlumessa.com and we will look into it.
You can also complain to the Information Commissioner's Office, the UK's data protection regulator, at ico.org.uk or on 0303 123 1113. If you are in the European Union you may instead complain to the supervisory authority in your own country.
Age
Lumessa is for people aged 13 and over. We do not knowingly hold personal data about anyone younger, and if we learn that we do, we delete it.
Changes
If what we do changes, this notice changes with it, and the date at the top changes too.