Privacy Policy

Last updated 30 August 2026

The short version

Starlit has no accounts, so it never learns your name or your email address. Your books, your reading history and your questions stay on your device. When you highlight a passage and ask about it, that passage and a little of the writing around it are sent away to be explained. Nothing else is.

What Starlit never collects

No name. No email address. No password. No location. No advertising identifiers. No analytics. No third-party SDKs. No tracking, of any kind.

Your books are never uploaded. An EPUB you import stays on your device. Only short extracts leave it, and only when you ask for something.

How you are identified

Starlit identifies you by an opaque identifier that iCloud assigns to this app. It is not your Apple ID, your name or your email address, and it cannot be traced back to any of them.

It exists for one reason: so the credits you have bought survive reinstalling the app, and follow you to your other devices.

It is stable, so it is tied to you across sessions — we would rather say that plainly than call it anonymous. What it is not is identifying: it tells us nothing about who you are.

What is sent when you ask a question

When you use Explain or Ask, this is sent to our server and on to our AI provider:

• the text you highlighted
• the sentence fragments on either side of it, and the paragraph before and after
• the book’s title and author, and the chapter title
• your question, if you typed one
• your identifier, and your device’s language

The surrounding paragraphs are the point. The same sentence means different things in different places, and an explanation written without them is the dictionary entry you were trying to get away from.

When you use Speak, the selected text and the voice you chose are sent, and nothing else. When you add a book, its title, author, chapter titles and your own category names are sent so it can be shelved.

All of it travels over an encrypted connection.

Our server records the time and the internet address of requests in its logs for about a week, the way any web server does. Those logs contain nothing about what you read or asked.

If you would rather nothing left your device at all, the system dictionary, Apple Translate and the built-in iOS voice work entirely offline and cost no credits.

When Starlit searches the web

When an answer needs something the book does not contain, Starlit searches the web. The search uses words drawn from the passage you highlighted and the question you asked, and the pages it finds are read to compose the answer.

Those websites are visited by the AI provider, not by your device. They receive nothing that identifies you.

Who processes it

Explanations, answers and speech are generated by OpenAI. Three things get confused with one another here, so they are worth separating:

• Nothing is kept in an OpenAI log that we can read. Requests are sent with retention switched off, so they never appear in our OpenAI account.
• Nothing is used to train OpenAI’s models. This project is excluded from OpenAI’s sharing of inputs and outputs.
• OpenAI keeps its own copy for abuse monitoring, for up to 30 days, regardless of either of the above. That is OpenAI’s policy rather than ours, and it applies to every customer of their API. You can read it in OpenAI’s data controls documentation.

Purchases

Credits are bought through Apple’s In-App Purchase. Apple takes the payment. Starlit never sees your card details, your billing address or your Apple ID.

Our server receives Apple’s signed receipt and grants the credits it is worth. We keep the transaction identifier permanently, so the same receipt cannot be redeemed twice.

Your purchase history belongs to Apple, and you can see it in the App Store under your Apple ID.

What stays on your device

• The books you import.
• Every lookup, question and answer. Your reading history never leaves the device and is never synced.
• Generated audio, cached per voice — which is why replaying something costs nothing.
• Your settings.

Deleting the app deletes all of it, permanently. Your credit balance is the one exception: it lives on our server, so reinstalling brings it back.

Deleting your data

Starlit has no account to delete. What our server holds is the identifier described above, and counts of credits bought and spent. No name, no email address, and nothing you have read, highlighted or asked.

That record stays when you delete the app, deliberately: its existence is what stops the free starting credits being claimed again and again by reinstalling. We keep a record that those free credits were issued, for the same reason.

Because we hold nothing that identifies you, we cannot find one person’s record on request — there is no name or address to look you up by. Your purchase history is held by Apple and managed through your Apple ID.

Children

Starlit is not directed at children under 13, and we do not knowingly collect anything from them.

Changes to this policy

If this policy changes, the date at the top of the page changes with it.

How to reach us

Email starlit@side-project.me. A person reads it.