Privacy policy

Last updated: 14 September 2026

Who is responsible

HeyPlumi is a project of Heliocentrium, which decides how this data is handled. Its identifying details are in the legal notice. For anything about privacy, write to privacidad@heyplumi.app.

What this policy covers

Two separate things: this website (heyplumi.app) and the HeyPlumi mobile app for iOS and Android, together with the server behind it.

This website

It is hosted on Microsoft Azure, in the European Union, which records HTTP requests in its own technical logs, as any web server does. Visiting it does not require giving us any data.

The waitlist

If you join the waitlist we keep your email, the language of the page you joined from, which phones you use (iPhone, Android or both), and the date. We do not keep your IP address: to stop abuse we only use an irreversible fingerprint of it that does not reveal what it is.

We use it only to write to you when HeyPlumi can be downloaded (on the App Store or Google Play, depending on your phone). The legal basis is your consent (GDPR art. 6(1)(a)). When you join we send you a confirmation email, and every email carries an unsubscribe link that deletes your entry immediately. You can also ask at privacidad@heyplumi.app.

Entries are stored on Microsoft Azure, in the European Union, and emails are sent with Azure Communication Services, with data in Europe and no open or click tracking. We keep your entry while the waitlist exists or until you unsubscribe.

Cookies and analytics on the website

The website only uses cookies if you accept them in the notice shown when you arrive. If you accept, it loads Google Analytics 4 (Google Ireland Limited) to learn, in aggregate, how many people visit, where they come from and which sections they read. Google Analytics uses the _ga and _ga_* cookies, which last up to 2 years, and the data is kept for 14 months.

If you decline, nothing from Google is loaded and no cookie is set. Your choice is kept in your browser’s local storage so we do not ask again, and you can change it at any time from “Cookies” in the website footer. If you switch language with the ES/EN selector, the language you picked is kept there too; it is not a cookie and never leaves your browser.

Your account: Google or Apple

The app needs an account, because your vocabulary is also kept on our server. You sign in with Google or Apple; there are no HeyPlumi passwords and we store none.

Sign-in is handled by Auth0 (by Okta, Inc.), which sits between Google or Apple and us. Auth0 receives the basic profile data Google or Apple share when you sign in — such as your name and email — and passes us an identifier for your account, your email, whether it is verified and, if present, your name. If you use Apple’s “Hide My Email”, what we receive is Apple’s relay address, not your real one.

What we keep on our server

• Your account: the identifier the sign-in provider issues, your email and whether it is verified, the name the provider sends, and when the account was created.
• Your profile: the name you want us to call you (required), your surname (optional) and your date of birth (optional).
• Your vocabulary: your languages and dictionaries, and every word you save with its senses, translations, examples, synonyms and your personal notes, plus which language you chose to file it under.
• Your practice: the review state of each word (where it stands, when it is due again, right and wrong answers) and a summary of each day you practise: how many you reviewed and how many you got right.
• Your settings: native language, reminder time, theme, haptics, daily goal and whether you have completed the app’s introduction, among others.
• Your devices: a random identifier generated by the app, the platform (iOS or Android), the app and operating-system versions, the difference between the phone’s clock and the server’s, and when it last connected.
• Technical sync data: the history of changes and, when two devices edit the same thing at once, both conflicting versions. They exist so all your devices end up with the same thing.

When you look up a word

To give you a word’s card, the app sends the word to our server, which looks it up in our dictionary. That lookup is not stored in your account: only what you choose to save becomes part of your vocabulary. Server logs never include the word you looked up.

If the word is in a language you are learning and is not in our dictionary, the server may ask Azure AI Translator, a Microsoft service we use in the West Europe region, for the translation. It receives only the word and the language pair, never who you are.

When a word is not found anywhere, we count how often it has been looked up — the word, the language, the count and the dates — without linking it to any person, to decide what to add to the dictionary.

What stays on your phone

• Your search history. This is an architectural decision: that table is never synced and has no counterpart on the server. The words you save say what you are learning; the words you look up say what you do not know, and that can reveal a lot about a person. Reinstall the app and that history is gone.
• The daily reminder. It is a notification scheduled on the phone itself. There is no push server and no push token. The operating system asks for permission, and you can withdraw it at any time.
• Pronunciation. It is read aloud by your phone’s system voice (iOS or Android). The app does not send that text to any server of ours.

App updates

The app may download updates from the EAS Update service by Expo (650 Industries, Inc., United States). That request carries technical data — IP address, platform and app version — but not your account or your words.

What we do not do

We do not collect your location, your contacts or advertising identifiers (IDFA/AAID). The app ships no third-party analytics, advertising or crash-reporting SDK. We do not sell your data or share it with anyone for advertising.

Why, and on what legal basis

• Providing the service — creating and keeping your account, saving and syncing your vocabulary, preparing word cards and handling your requests: necessary to provide the service you ask for by using the app (GDPR art. 6(1)(b)).
• Surname and date of birth: optional, and handled because you choose to give them (consent, art. 6(1)(a)). Today the date of birth is only kept in your profile; it is not used to decide anything and is not shared. You can leave them blank or ask us to delete them.
• Security and running the server — technical logs, abuse limits — and the anonymous count of words not found: legitimate interest in keeping the service secure and useful (art. 6(1)(f)).
• The daily reminder: only if you turn it on and grant the system permission.
• The waitlist and website analytics: your consent (art. 6(1)(a)), which you can withdraw at any time.

Who else handles your data

Only providers we need for the app and the website to work, each with the bare minimum:

• Google or Apple, whichever you sign in with. You have your own relationship with them, governed by their policies.
• Auth0 (Okta, Inc.), which handles sign-in. Its service for HeyPlumi is located in the United States.
• Microsoft Azure, which hosts our server, the database, the technical logs, Azure AI Translator, this website with its waitlist, and email sending (Azure Communication Services), in data centres in the European Union.
• Google (Google Ireland Limited), only on the website and only if you accept analytics cookies: Google Analytics.
• Expo (650 Industries, Inc.), for app updates.

Transfers outside the European Union

Our server and your vocabulary are in the European Union. The sign-in data handled by Auth0 and the update request to Expo are processed in the United States. Those transfers rely on the safeguards each provider offers, such as the Standard Contractual Clauses approved by the European Commission. If you accept analytics on the website, Google may process that data in the United States under the EU-U.S. Data Privacy Framework.

How long we keep it

• For as long as you have an account.
• If you ask to delete it, there is a 30-day grace period. Signing in again within that period cancels the deletion. After 30 days, an automatic process that runs every day permanently deletes everything your account holds on our server. Details on Delete your account.
• Database backups are kept for 7 days, so deleted data can remain in them for up to 7 more days, until they are replaced.
• Server technical logs (IP address, time, the address requested and the result; never the words you look up or your credentials): 30 days.
• Proof of deletion: we keep an internal identifier and the dates the request was made and carried out, without your email or your content, as evidence that we honoured it.
• Your Auth0 record (identifier, name and email) is not deleted by that automatic process. If you want it removed too, ask us and we will delete it.
• On your phone, everything is removed when you delete your account from the app or uninstall it.

Security

All traffic between the app and the server is encrypted (HTTPS). The database is encrypted at rest, and each account can only read its own data — enforced by the database itself, not just by the code. We store no passwords. On the phone, your session is kept in the system’s secure storage (Keychain on iOS, Keystore on Android), and iOS and Android isolate the app’s data so other apps cannot read it.

Your rights

You can ask us at any time for access to your data, to rectify it, to erase it, to restrict its processing, to object to it, and to receive a copy in a reusable format (portability). Where we rely on your consent, you can withdraw it whenever you like.

To delete your account, use the option inside the app. For anything else, write to privacidad@heyplumi.app from your account’s email address, so we can check it is you. We reply within one month at most.

If you believe we have not handled your data properly, you can complain to the Spanish data protection authority, the Agencia Española de Protección de Datos (www.aepd.es).

Children

You must be at least 14 to use HeyPlumi, the age from which Spanish law lets you give consent yourself. Date of birth is optional and we do not verify age; if we learn that an account belongs to someone under 14, we delete it. If you are a parent or guardian and think this is the case, write to us.

Changes

When this policy changes, the date in the header changes with it. Significant changes will also be announced inside the app, not only here.

Contact

Write to privacidad@heyplumi.app.