Privacy

Effective date: November 2, 2026. Plain language, no fine print. Open Book is built for personal, on-device use: what you block and what you do stays on your iPhone.

What stays on your device

Your blocking choices (the apps, categories and websites you pick), app exceptions, pause state, Activity log, 30-day challenge, weekly recap, any reasons you pick during setup or type on the urge screen, and whether you made the 30-day promise during setup are stored on your iPhone. You can delete your reasons on the urge screen, and deleting your account deletes your reasons and the promise. Blocking runs through Apple's Screen Time controls on your device. Open Book does not use a VPN, does not inspect your traffic, and never sends the websites you visit, the apps you use, your Screen Time data or your Activity log to our servers or to anyone else. The weekly recap is a local notification built on your iPhone.

What our server stores

To run your account and any existing subscription, our server keeps only:

• An account identifier — a random user ID created for your account.
• A device identifier — a random ID the app generates to register your account. No email address, name, phone number or password is asked of you.
• Purchase records, if you bought Strict mode — its status, plan, renewal date for a subscription, and your RevenueCat customer ID.

The account is used to restore purchases, to count subscription events (see PostHog below) and to let you delete your account.

Who we share with

We use these service providers:

• RevenueCat — processes and restores purchases and subscriptions. It receives your account ID and purchase history from Apple's App Store. From version 1.0.7, the app sends RevenueCat a token from Apple's AdServices framework. RevenueCat uses it to ask Apple whether an Apple Search Ads campaign led to the download and, if so, which campaign, ad group and keyword. We use this only to count which ads lead to subscriptions. It uses no advertising identifier and does not track you across other companies' apps or websites.
• PostHog — receives a small number of account and subscription events from our server (account created, subscription changes, account deleted), linked to your account ID, or to RevenueCat's random customer ID if you subscribed before your account was set up, which we use to understand subscriptions. It also receives server error types that are not linked to you. From version 1.0.3, the app also sends PostHog a few anonymous usage events, such as blocking turned on or off, a challenge started or finished (with its number of kept days), the weekly recap turned on, the subscription screen shown, and from version 1.0.7 a subscription bought or failed (with its plan: annual, monthly or lifetime) or restored, and from version 1.0.8 the urge screen opened, along with the app version, iOS version and device model. These events use a random analytics ID that is not linked to your account, and they never include websites, app names, your Screen Time data or your Activity log. PostHog receives the network address each request comes from, and the app turns off location lookup from it.

The app contains no crash-reporting or advertising SDKs. We do not sell your data, show ads, or track you across other companies' apps or websites. Apple processes payments under its own privacy policy.

This website

If you reach useopenbook.com from a ChatGPT or OpenAI link, the site sets one cookie, ob_src, that holds only the word "chatgpt" and expires after 30 days. While it is set, the site's App Store links carry Apple's campaign tag "chatgpt", so App Store Connect can tell us how many downloads came from ChatGPT. The cookie holds nothing else and is not shared with anyone. When you tap a download button, our server counts the click by page name, plus "chatgpt" if you came from ChatGPT. That count holds nothing about you.

Records from earlier versions

Earlier versions of Open Book could share protection status with people a user invited, which stored event types and times, device check-in times, an invited person's email and mobile number (encrypted), and status alerts. The current version does not include these features and does not upload any of this information. Text alerts from earlier versions are no longer sent. Earlier versions also use an email provider to send password-reset links. We never sell or share mobile numbers or text-message opt-in data. Mobile information and messaging consent are not shared with third parties or affiliates for marketing or promotional purposes. Event records are deleted automatically after 90 days. Other records from earlier versions are kept until you delete your account.

Keeping and deleting your data

We keep your account and subscription records while you have an account. You can delete your account at any time in the app under Settings > Account & subscription > Delete account. This permanently deletes your account and all records about it on our server. Purchase records held by RevenueCat and events already sent to PostHog are not deleted by this step; email us to ask for their deletion too. Data on your iPhone is removed when you delete the app. Deleting the app or your account does not cancel an Apple subscription; manage that in iPhone Settings > your name > Subscriptions.

You're in control

You can stop blocking in the app, or turn off Screen Time access in iPhone Settings, at any time — you're never locked out of your own device. Open Book is intended for adults and is not directed at children.

Changes and contact

If we change this policy, we will post the new version here with a new effective date. Questions or requests: Reno Labs, LLC, [email protected].

Questions? Visit Support or read our Terms.