Privacy Policy

Last updated: September 2026

Lumin is a devotional app. What you write in it is personal. This page describes what the app collects, how it collects it, everything it is used for, and every third party it is shared with — including the AI service that generates Lumin’s replies.

You do not need an account

Lumin is usable without registering. On first launch the app creates an anonymous identity for your device so that your reading, journal, and conversations have somewhere to live. That identity holds no name, no email address, and no password — it is a random identifier and nothing else.

Creating an account is optional. It adds your email address, and a name if you give one, and in exchange it lets you reach your content from your other devices, recover it if you lose your phone, and use the download and delete controls described below. A Lumin Pro subscription does not require an account; Apple ties the purchase to your Apple ID, and an account only matters if you want the subscription’s content on a second device.

What we collect, and how

Account information — your email address, and a display name if you set one. Collected from what you type on the sign-up screen, and only if you choose to register.
Content you write — journal entries, prayers, notes, highlights, and your messages to Lumin. Collected as you save them in the app.
Voice recordings — only if you use voice input, and only for as long as it takes to turn the recording into text. Collected from your microphone, after iOS asks your permission.
Reading position and app settings — where you left off, and your study preferences (tone, depth, reading level). Collected from your use of the app and from the settings screens.
Usage counts — which features are opened, and how many AI requests you have made, so the daily limits can be applied. Collected automatically as you use those features.
Subscription status — whether Pro is active, and the App Store receipt that proves it. Collected from Apple through RevenueCat. We never see or store your card details.
Crash and error reports — the technical details of a failure, collected automatically when the app crashes, and used to fix the defect.

Lumin does not collect your location, contacts, photos, health data, or advertising identifiers, and it does not track you across other apps or websites. There is no analytics SDK in the app.

How we use it

To provide the features you ask for, including generating Lumin’s replies
To keep your content available to you, and to sync it across your devices if you register
To open the app where you left off, and to honour your study preferences
To apply the daily limits on AI requests fairly, and to prevent abuse of them
To deliver the reminders you have turned on — these are scheduled on your device, and their contents never leave it
To send transactional email you have asked for, such as a password reset or a copy of your data
To diagnose crashes and fix defects
To answer you when you contact support

That is the complete list. Lumin does not sell personal information, does not share it for cross-context behavioural advertising, does not use it to build advertising profiles, and does not use your content to train any AI model of ours.

The AI features, and the third-party AI service

Lumin’s AI features are powered by OpenAI, a third-party AI service in the United States. Requests go to OpenAI’s API — today that is the gpt-4o-mini model for written replies and insights, and whisper-1 for turning voice input into text.

Nothing is sent to OpenAI until you have given permission. The first time you use an AI feature, Lumin shows a screen that names OpenAI, states what the data is used for, and lists exactly what would be sent. It is off until you turn it on. You can withdraw permission at any time in Settings → AI & Privacy, and once it is off nothing further is transmitted — the refusal is enforced in the app’s network layer, not merely in the screens, so no part of the app can send anything without a current grant.

When permission is on, what is sent to OpenAI is:

The message you type or speak to Lumin
Earlier messages in that same conversation, so replies follow the thread
The passage or devotional you are reading, when it is relevant to what you asked
Your study preferences — tone, depth, and reading level
Your voice recording, if you used voice input, so that it can be transcribed
The text of a specific journal entry, prayer, or note — only when you ask for insight on that item, by tapping the action that requests it. Saving an entry does not send it. Nothing is sent from your journal or prayer list in the background, and nothing is sent when the AI setting is off.

What is never sent to OpenAI:

Your name, email address, or account credentials
Your payment details or App Store receipt
Your journal, prayers, or notes other than the one item you asked about

OpenAI acts as a processor on Lumin’s behalf under their API data-processing terms. Under those terms your content is not used to train their models, and we have confirmed that the protections they provide for this data are equivalent to those described in this policy. Voice recordings are sent for transcription and are not retained by Lumin once the text comes back.

Everyone else we share it with

Lumin uses a small number of processors. Each receives only the data it needs, may use it only on Lumin’s instructions, and is bound by terms providing protection equivalent to this policy. None of them sells your data.

Supabase — database hosting and sign-in. Your identity, content, reading position, and settings are stored here.
Railway — hosting for Lumin’s own server, which your requests pass through.
OpenAI — the AI features, as described above, and only with your permission.
RevenueCat — checks your subscription status with Apple. Payment itself is handled by Apple, not by us.
Resend — delivers transactional email, such as a password reset or a data export.
Sentry — receives crash and error reports.
bible.helloao.org — supplies public-domain commentary text. The app asks it for a book and chapter; it receives no account information and nothing you have written.

We will also disclose data if the law requires it. We will not hand over your journal, prayers, or conversations to anyone else.

These companies are all based in the United States, so if you use Lumin elsewhere your data is transferred to and processed there.

How long we keep it

Content you write is kept until you delete it, or until you delete your account. Voice recordings are discarded as soon as they have been turned into text. Usage counts are kept only as long as the limit period they enforce. Crash reports are kept only while they are useful for fixing the defect that produced them.

Deleting your data

If you have an account, you can delete it and everything in it from inside the app, at any time, without contacting us: open Profile, then Privacy, then Delete Account, and confirm. The same screen can email you a copy of your data first.

Deleting your account permanently erases:

Your account and profile information
Your reading history
Your AI conversations
Your notes and highlights
Your settings and preferences

This cannot be undone. Deleting your account does not cancel an active subscription — cancel that in your Apple ID settings, since Apple, not Lumin, manages the billing relationship.

If you never registered, the download and delete controls are not shown, for a plain reason: an anonymous identity holds no email address or name, so we have no way to tell that a request from you concerns that identity. Deleting the app stops all further collection. Registering attaches your existing content to you and turns the controls on, without losing anything you have already written.

Security

Your data is encrypted in transit and at rest, and your sign-in session is held in your device’s secure keychain. Access to production data is restricted. To be exact about what that does not mean: Lumin is not end-to-end encrypted. Our servers can read your content, because generating an insight on a journal entry requires reading the entry.

Your rights

Depending on where you live, you may have the right to access, correct, export, or erase your personal data, to object to or restrict certain processing, and to withdraw consent. Withdrawing AI permission is in Settings → AI & Privacy. Access, export, and erasure are in Profile → Privacy once you have an account. For anything else, email the address below and we will respond within 30 days.

Children

Lumin is not directed at children under 13, and we do not knowingly collect personal information from them. If you believe a child has given us personal information, email us and we will delete it.

Changes

If this policy changes materially, we will update the date at the top of this page and, where required, ask you again in the app — including if the AI provider ever changes, since permission to send your words to OpenAI is not permission to send them somewhere else.

Contact

Questions about this policy: luminbiblecore@gmail.com