Shelf Circle Privacy Policy

Last updated: September 25, 2026

Shelf Circle is a friends-only app for tracking what you read and sharing book recommendations with people you know. This policy explains what information the Shelf Circle Android app (package com.shelfcircle.app) and its servers collect, why, who can see it, and how you can delete it. It applies to Shelf Circle only, not to other projects on this site.

Shelf Circle is made by culpeo-labs ("we", "us"). To reach us about this policy or your data, use the privacy contact form (see Contact).

The short version

• You sign in with your email. We store your email, a profile (handle, display name, optional photo), and the reading data you enter.
• Your friends — people you invited and who joined, or whom you approved — can see your name, handle, photo, and reading activity. They can see your full bookshelves only if you turn that on. Nobody else can look you up.
• We don't show ads, we don't sell your data, and we don't use analytics or advertising trackers.
• You can change or delete your information at any time. See Your choices and deleting your data.

Information we collect

Information you give us

What	Why we need it
Email address, and the sign-in credentials you choose (a one-time code, a password, or a passkey, depending on how sign-in is configured)	To create your account and sign you in. Credentials are handled by our sign-in provider, Hanko (see Service providers); we never see or store your password. We receive and store your email address.
Profile: handle (username), display name, and an optional profile photo	To identify you to your friends.
Reading data: the books you add, the shelf each is on (want to read, reading, finished, did not finish), reading progress, star ratings, when you finish a book, and whether you logged it as something you read before using the app	To run the app: your shelves, your timeline, and your yearly reading count.
Reading goals you set (for example, "24 books in 2026")	To show your progress.
Friends, invites, and recommendations: who you are friends with, invite links you create, and recommendations you send or receive, including any note you write (up to 280 characters)	To connect you with friends and deliver recommendations.
Your library: which public library system you chose (for example, Seattle Public Library)	To link book pages to that library's catalog.
Settings: whether you share your bookshelves with friends	To respect your choice.

Information from your device

• Time zone. The app sends your device's time zone so your yearly reading count changes over on New Year's Day where you live. We store it alongside a reading goal if you set one.
• Camera (only if you scan an invite). The app asks for camera permission to scan a friend's invite QR code. Camera images are processed on your device to read the code; they are not stored or uploaded. You can decline, and open the invite link instead.
• Photos (only if you choose a profile picture). The app uses Android's photo picker, so it can access only the single image you select. The image is cropped and resized on your device, then uploaded as your profile photo.
• Sign-in session. Your sign-in token is kept in your device's secure storage so you stay signed in. The app also remembers, on your device, when you last looked at your recommendations (for the unread badge).

Technical information

Like most online services, our servers and hosting provider process technical information needed to deliver and protect the service, such as your IP address, the time of a request, and error details. Application logs are kept for up to 30 days.

What we don't collect

We do not collect your location, contacts, advertising ID, or browsing activity. The app has no advertising and no third-party analytics or crash-reporting tools.

How we use your information

We use your information only to provide and secure Shelf Circle: to sign you in, show your shelves and timeline, connect you with friends, deliver recommendations, count your yearly reading, look up books and library links, fix problems, and prevent abuse. We don't use it for advertising or to build marketing profiles, and we don't sell it.

Who can see your information

• Your friends. Friends are added only through an invite link or QR code that you create (see below). Your friends can see your display name, handle, and photo, and your reading activity in their timeline (for example, that you started or finished a book) — except books you log as read before you started using Shelf Circle, which are kept out of the timeline. Friends also see the recommendations you send them, including your note. You can only send recommendations to your friends.

• Your bookshelves, if you choose. By default only you can see your shelves. If you turn on Share my bookshelves with friends (Me tab), your friends can see what you are reading, have read, and want to read, with your ratings and progress. You can turn this off at any time.

• Your reading goal and yearly count are visible only to you.

• People who aren't your friends can't search for you or look up your profile. Your email address and account ID are never shown to other users, and your handle is shown only to your friends.

• Invite links. You choose how each invite works:

  • One person: a link or QR code that works once and expires after 7 days. Whoever uses it first becomes your friend straight away, so share it only with the person you mean.
  • Anyone with the link: a link that works for up to 30 days, or until you stop it, for sharing more widely. Each person who uses it sends you a request that shows only their display name and photo, and they become your friend only if you approve.

  Anyone who has an invite link before it is used up or expires can see your display name and photo (and whether approval is needed), so treat it like a private link.

• Your profile photo is stored at a web address that isn't listed anywhere but that anyone who has the address can open. When you replace or remove your photo, we delete the old file. If you pick a photo and leave without saving, we delete that unsaved file within a couple of hours. Deleting your account removes your photos.

Service providers

We use a small number of companies to run Shelf Circle. They handle information only to provide their service to us, not for their own purposes.

• Hanko (hanko.io) provides sign-in. It processes your email and sign-in credentials and issues the token that proves who you are.
• Microsoft Azure hosts our servers, our database, and profile-photo storage. Our data is hosted in the United States (Azure West US). Azure encrypts stored data at rest.
• Book and library lookups. When you search for a book, your search text is sent from our servers to Open Library (Internet Archive) and, when enabled, Google Books. When you open "Get it at your library", the book's title, author, and ISBN are sent from our servers to your library's online catalog (currently BiblioCommons-hosted catalogs) to find the book. These requests come from our servers and don't include your name, email, or account. Tapping the resulting link opens the library's own website in your browser, which is covered by that library's privacy policy.
• Tally (tally.so) hosts our privacy contact form. What you type into that form (your email address and your message) is processed by Tally on our behalf under its data processing agreement. Tally states that its service is hosted in the EU.
• Google Play distributes the app and collects its own information under Google's privacy policy.

We may also disclose information if the law requires it, or to protect the safety of our users or our service.

How long we keep your information

We keep your information while your account exists. When you delete your account, we delete it straight away: your profile, profile photos, bookshelves, ratings, reading history, goals, friends, invites, and recommendations (including ones you sent to other people), and your sign-in account with Hanko, including your email address. Encrypted database backups are kept for up to 7 days and then expire, and application logs for up to 30 days, so residual copies can persist for that long after deletion.

For 7 days after deletion we also remember an anonymous account identifier (no name or email), so that a sign-in session that was still active can't quietly re-create the account you just deleted. Then that identifier is deleted too.

Your choices and deleting your data

• Edit or remove your information. In the app you can change your display name and photo, remove your photo, change or remove your reading goal, and choose whether friends see your bookshelves.
• Delete your account and data. In the app, open the Me tab and choose Delete account, then confirm. Everything described above is deleted immediately, and you are signed out. If you can't get into the app, send a request through the privacy contact form with the subject "Delete my Shelf Circle account" and the email address on your account, and we'll delete your account and all data, including your sign-in record with Hanko, within 30 days and confirm by email.
• Access or correct your information. You can see most of it in the app. If you'd like a copy of the rest, or something corrected, email us.

If you live somewhere that gives you rights over your personal information (for example, the EU/UK, or California), you can use the same email address to exercise them. We don't sell or "share" personal information for cross-context advertising.

Security

Everything between the app and our servers travels over encrypted connections (HTTPS). Passwords are handled by our sign-in provider and never reach our servers. Your sign-in token is kept in your device's secure storage. No system is perfectly secure, so we can't promise absolute security, but we work to protect your information and will tell affected users if a breach puts their information at risk.

Children

Shelf Circle is not directed to children, and you must be at least 16 to use it. We don't knowingly collect information from anyone under 16. If we learn that an account belongs to someone under 16, we delete it. If you believe a child has given us information, use the privacy contact form and we'll delete it.

International users

Our servers are in the United States. If you use Shelf Circle from elsewhere, your information is transferred to and processed in the United States.

Changes to this policy

We'll update the date at the top when this policy changes. If a change is significant, we'll tell you in the app or by email before it takes effect.

Contact

For questions or privacy requests, use our privacy contact form (hosted by Tally).