KRIZ Privacy Policy

Effective 3 August 2026.

KRIZ is a reading-diary app. This page explains, in plain words, what data the app handles and what happens to it.

In short: your diary lives on your phone. An account is only needed if you want your entries on more than one device, and it is needed by no one else.

Who is responsible for your data

The developer of KRIZ. Contact: [email protected].

What is stored on your device

Everything you write in the app: books, ratings, reviews, quotes, thoughts, questions, observations, characters, “After the book” material, shelves, reading dates, your chosen language and appearance, and your profile photo if you set one.

This is kept in a database on the device itself. Without an account it is never sent anywhere. Deleting the app deletes it — which is why Profile offers a backup to a file.

What is sent if you create an account

The account is optional. It exists only for syncing between devices.

Your email address. It is the only thing we store about you, and it is

Diary content: books, entries, characters, material and shelves. These

what lets you get back to your entries. There are no passwords: a one-time code is emailed for each sign-in.

are stored on Supabase servers (our database provider) and are reachable only by your account — enforced by row-level security in the database.

Your profile photo, language and appearance are not synced and stay on the device.

Where book searches go

When you search for a book or scan a barcode, the query text (title, author or ISBN) is sent to the public catalogues Google Books and Open Library to retrieve the title, author, cover and description.

Your email address, your diary content and any identifier of yours are not sent with those queries.

Camera and photos

The camera is used only to read the barcode on a book cover. No picture

The photo library opens only when you choose a picture for your profile

is stored or transmitted — only the number is recognised.

yourself. The picture stays on the device.

What we do not do

no advertising;
no behavioural analytics or tracking SDKs;
no sharing or selling of your data;
we do not read the contents of your diary.

Service providers

Supabase — account storage and syncing.
Resend — delivery of one-time sign-in codes by email.
Google Books and Open Library — book catalogues.

How to delete your data

Your account: Profile → Delete account. Server-side data is removed.

Data on the device: delete the app.
If something does not work, write to [email protected].

The diary on your device is left untouched — you are removing entries from the server, not erasing your own memory.

Children

The app is not directed at children and does not knowingly collect data from children under 13.

Changes

If this policy changes, the new version will be published at this same address with a new date. Significant changes will also be announced in the app.