Last updated 25 August 2026
Ilusi is a reading app. It is built so that we know as little about you as possible, and this page describes exactly what that means rather than reserving rights we do not use.
Ilusi does not ask for your name, your email address or a password, and there is nothing to sign up for. When you first open the app it asks our server for an identity, and the server issues a random identifier that means nothing outside Ilusi. That identifier owns your credits and your illustrations.
Because there is no account, we cannot tell you who you are, and neither can anyone else who obtains our database. The trade is that your credits live on the device: if you lose it, we have no way to identify you and restore them.
To work out which passages are worth illustrating, Ilusi reads through the book once. The text is sent to our server, held in memory for as long as that pass takes, and then discarded — we do not keep a copy of your book, and there is no feature that would let us or anyone else read it back. It is also passed to an AI provider during that same pass; see below, because that part matters.
What we do keep is what the pass produced: short descriptions of the scenes to be illustrated, their captions, descriptions of the characters, and the instructions used to draw each picture. These are derived from your book and can quote or paraphrase small parts of it. They are kept so that your illustrations stay consistent from chapter to chapter, and so that you are not charged twice for the same picture.
Your library, your reading position and your progress stay on your device and are never uploaded.
This is the part worth reading carefully, because it is the least obvious. Ilusi cannot work out which passages are worth illustrating without a language model reading them, and we do not run that model ourselves. During the one-time pass, the text of your book is sent — a chapter at a time, and over the course of the pass essentially all of it — to a third-party AI provider: Google's Gemini models, reached through OpenRouter. A full-length novel is a few dozen such requests.
Neither we nor they keep your book as a book. But it does travel through their systems, and what they do with it while it is there is governed by their terms, not ours. If a book is private or sensitive to you, that is the fact to weigh before turning illustration on for it.
Drawing the pictures is different and sends far less: only the short scene description produced by that first pass, with character and place names removed, so the image model receives a description of a scene rather than an identifiable work.
Nothing is sent anywhere until you ask Ilusi to look at a book. Reading a book you never illustrate involves no upload at all.
When the app first asks for an identity it sends the identifier your operating system provides to apps (the vendor identifier on iOS, the Android ID on Android). We store only a one-way hash of it, and it is used for exactly one purpose: making sure a single device cannot claim a welcome offer more than once.
It is not used to track you, to build a profile, to link you across apps, or for advertising.
Credits and the Ilusi Pro upgrade are bought through Apple's App Store or Google Play. Your payment details go to them and never reach us. We receive confirmation that a purchase happened, and we record which product it was and its transaction identifier so that the same purchase cannot be applied twice.
Ilusi contains no analytics library, no crash-reporting service, no advertising network and no third-party tracker. We do not know which books you read, how long you read for, or whether you opened the app today.
Our server keeps operational records of illustration requests — when one was made, which style, how long it took, what it cost us, and whether it succeeded or was refused — so that we can keep the service working and priced honestly.
Ilusi is not directed at children under 13, and because there is no account we do not knowingly collect information from them.
You can remove everything held on your device by deleting the app. To have the illustrations and records tied to your identifier deleted from our server, write to privacy@ilusi.app from the device in question and include the identifier shown in the app's Credits screen. We will delete them and confirm.
Deleting the app alone does not remove what is on the server, because we have no way of knowing you did it.
If this policy changes in a way that affects what we collect or who we send it to, the app will say so before the change takes effect, rather than quietly updating this page.
Questions about privacy: privacy@ilusi.app. Anything else: hello@ilusi.app.