About this policy#
This policy explains how the CS Revision app for iPhone and iPad (“the app”) and this website handle information. The app and website are made and run by Grigor Dochev, an independent developer (“we”, “us”). We are the data controller for the small amount of personal data described here, such as an email you send us.
The policy applies to version 2.0 of the app and later. Account data from the earlier version 1 is covered in Data from version 1 of the app. You can reach us about anything in this policy at gdoch9@gmail.com.
What the app does not do#
The app is built so that we never need to see your study data.
- There is no account or sign-in, and the app never asks for your name, email address, age, school or location.
- There is no advertising and no tracking. The app does not use the advertising identifier or follow you across other apps or websites.
- There are no third-party analytics, advertising, crash-reporting or AI services built in. The app uses only Apple’s own frameworks.
- We run no server for the app. Lessons and questions are bundled inside the app, and nothing you do in it is sent to us.
- We never sell, rent or share personal data for marketing.
Information the app stores#
To work, the app keeps the following information. It stays on your devices and, where noted, in your own private iCloud storage (see iCloud sync). We cannot access any of it.
| Information | Where it is kept | Why |
|---|---|---|
| Study profileCourse level (SL or HL), programming language (Python or Java), target exam year, daily study goal and whether you finished the welcome steps | Your device, synced through your private iCloud | To tailor lessons, examples and practice to your course |
| Study progressLessons read, how confident you rated yourself on each topic, topic mastery, question results, practice sessions, the answers you select or type, review dates and bookmarks | Your device, synced through your private iCloud | To show your progress and bring questions back for review at the right time |
| App settingsQuestion Coach preferences, whether the free Question Coach conversation has been used, your practice reminder setting and time, when the app last offered the App Store rating prompt, a first-launch marker, and the most recent campaign link record | This device only | To remember your choices and run these features |
| Due Review widget summaryThe number of questions due and their review dates | This device only, in storage shared just between the app and its widget | So the Home Screen widget can show what is due |
Your review schedule and mastery scores are worked out on your device to plan your revision. They are never used to make decisions about you outside the app.
iCloud sync#
If you are signed in to iCloud, your study profile and progress sync between your iPhone and iPad through the app’s private iCloud database. This database belongs to your Apple Account. Apple stores and protects it under the iCloud terms and Apple’s privacy policy, and the app can reach it only through your devices signed in to that account. We cannot see, download or change it.
If iCloud is not available, for example because you are not signed in or have turned off iCloud for the app, your study data is kept on that device and is not synced while iCloud is unavailable. You can check the current status in Settings → Data & Sync in the app.
Question Coach#
The Question Coach answers follow-up questions about the lesson or question you are studying. It uses Apple’s on-device language model, part of Apple Intelligence, through Apple’s Foundation Models framework. Your questions and its answers are generated and processed on your device.
- Conversations are kept in memory only while the Question Coach is open. They are not saved, logged, analysed or synced.
- Nothing you type into the Question Coach is sent to us.
- The study material it uses comes from the lessons and questions already inside the app.
The Question Coach needs a device that supports Apple Intelligence, with Apple Intelligence turned on. If you prefer not to use it, simply don’t open it; every other feature works without it.
Purchases#
Full Access is a one-time in-app purchase processed entirely by Apple through the App Store. Apple handles your payment details, receipts, refunds, offer codes and any Family Sharing. The app only checks with Apple whether your Apple Account has a valid Full Access purchase so it can unlock the paid features. We never receive your payment card details, and the app does not send purchase information to us.
Practice reminders#
Practice reminders are optional and off by default. The app asks for notification permission only when you turn them on in Settings → Practice Reminders. The reminder is a local notification scheduled by iOS or iPadOS on your device at the time you choose. No push service or third party is involved, and the schedule is not sent to us. You can change or turn off reminders, or withdraw notification permission in the Settings app, at any time.
Campaign links#
Some links, for example on this website or social media, can open a specific screen in the app. If such a link includes a campaign label, the app keeps one small record on your device: the campaign label, a general source such as “website” or “social”, the kind of screen opened and the date. A newer link replaces the older record. It is not linked to you, not synced to iCloud and never sent to us or anyone else.
Crash and performance reports#
If you have chosen to share analytics with app developers in Settings → Privacy & Security → Analytics & Improvements, Apple may give us crash reports and performance statistics for the app. Apple collects and prepares this data under its own policies and does not identify you to us. We use it only to find and fix problems. You can turn this off at any time in the same place.
The app also uses Apple’s MetricKit to note on your device which broad kind of problem occurred, together with the app and content versions. These notes stay in your device’s system log; the app does not upload them, and they never contain your questions, answers, prompts or anything that identifies you.
Support emails#
If you email us, we receive your email address, your name if your email shows it, and whatever you include in the message. We use this only to reply and help you. Our mailbox is provided by Google (Gmail), which stores email for us under its own terms.
Please don’t send passwords, payment details or other sensitive information. We keep support emails only for as long as we need them to deal with your request and keep a sensible record of it, and you can ask us to delete them at any time.
This website#
This website is a static site hosted by GitHub Pages. It uses no cookies, analytics, advertising, tracking or third-party scripts or fonts. Like any web host, GitHub may record technical information such as your IP address when you visit, to deliver and secure the site; see the GitHub General Privacy Statement. We do not receive visitor logs from GitHub.
Data from version 1 of the app#
Before version 2.0, the app (then listed as CS Revision) offered optional accounts and community features such as a forum and friends. If you created an account in version 1, your name, email address and a user ID were stored on the online service that version used, together with anything linked to your account in its community features.
Version 2.0 does not have accounts and does not read, use, transfer or migrate any version 1 data. If you had a version 1 account and would like a copy of its data or want it deleted, email gdoch9@gmail.com from the address you used for that account, or tell us which address it was. We will respond within one month.
Legal bases for processing#
Under the UK and EU General Data Protection Regulation (GDPR), we rely on these legal bases for the limited personal data we handle:
- Support emails and content reports: our legitimate interest in answering your request and improving the app’s content, or taking steps you ask us to take.
- Crash and performance reports from Apple: our legitimate interest in keeping the app reliable. Apple provides these only if you have opted in.
- Version 1 account data: our legitimate interest in responding to requests about that data and in closing the old service properly, and any legal obligation that applies.
Information that stays on your device or in your private iCloud is not processed by us.
Keeping and deleting your data#
Because your study data belongs to you and stays in your Apple ecosystem, you control how long it is kept:
- Reset your progress: Settings → Data & Sync → Reset All Progress deletes lessons read, topic and question progress, practice sessions and answers, review dates and bookmarks from your device and your private iCloud. Your other devices update when they next sync. Your study profile and Full Access purchase are kept.
- Remove everything from a device: deleting the app removes its local data, settings and widget summary from that device. Data already in iCloud stays there until you delete it.
- Remove data from iCloud: on iPhone or iPad, go to Settings → your name → iCloud and manage your account storage, where you can delete the app’s data if it is listed. Resetting progress in the app also removes progress records from iCloud.
- Exports: an exported file is your own copy. Delete it from wherever you saved or shared it.
- Support emails and version 1 data: kept as described in Support emails and Data from version 1. Ask us to delete them at any time.
Your rights#
Wherever you live, you can ask us what personal data we hold about you. If UK or EU data protection law applies to you, you have the right to:
- access the personal data we hold about you and get a copy;
- have inaccurate data corrected;
- have your data deleted;
- restrict or object to how we use it;
- receive your data in a portable format; and
- complain to a data protection authority, such as the UK Information Commissioner’s Office or the authority in your EU country.
To use these rights, email gdoch9@gmail.com. We will reply within one month and may ask for information to confirm the request is yours. There is no charge.
Because we hold no account or study data for the current app, most of these rights are in your hands directly: you can see your progress in the app, export it, reset it, or delete it as described in Keeping and deleting your data.
Children and young students#
The app is made for students, and many of them are under 18. It is designed to be safe for them to use: it has no accounts, no chat with other people, no advertising and no tracking, and we do not collect personal data through it. No parental consent is needed to use the app because no personal data is collected.
If you are under 16, or under the age of digital consent where you live, please ask a parent or guardian before emailing us or buying Full Access. Apple’s Family Sharing and Ask to Buy let parents approve purchases. If a parent or guardian believes their child has sent us personal information, contact us and we will delete it.
Security#
Your study data is protected by your device’s security and by iCloud. The app checks that purchases are verified by Apple, and this website is served only over HTTPS. Because we do not collect your study data, there is no central copy of it that could be exposed. No system is perfectly secure, so please keep your devices and Apple Account protected with a passcode and two-factor authentication.
Changes to this policy#
We will update this policy if the app or the way it handles information changes. The “Last updated” date at the top will change, and if a change is significant we will explain it in the app’s release notes before it takes effect. A future feature that needs new data will not be released until this policy describes it.
Contact#
Grigor Dochev is responsible for CS Revision. For privacy questions or requests, email gdoch9@gmail.com. For help with the app, see the support page.