Last updated: Sep 19, 2026
My name is Stéphan Barbé and I am the exclusive developer of Calculus Doodlus (“the app”) and the data controller for processing described in this policy. Your privacy is important to me and I am committed to providing you with a safe and enjoyable user experience. This Privacy Policy describes how your information is collected, used, and disclosed when you use the app.
Contact: info@stephanbarbe.de
I do not require you to create an account or to provide personal data such as your name, email address, location, or photos when using the app. I do not collect personal data directly on my own servers.
The app uses third‑party services that may process technical data on their own systems:
These services may process information such as an advertising identifier, basic device information, crash logs, and anonymous usage data. Under applicable privacy laws (including the GDPR), some of this technical information may be considered personal data. It is processed by the respective providers under their own privacy policies, for example: Google Privacy Policy and Apple Privacy Policy.
Where the GDPR applies, processing is based on:
The app displays ads using Google AdMob. AdMob may use cookies and similar technologies to collect information about your interactions with the app and other websites and apps to provide advertisements (including personalized ads when you have consented).
If you remove ads (for example via the Remove Ads annual subscription, Family Sharing, a temporary rewarded period, or a legacy purchase still covered by the thank‑you period), AdMob is not used and you will not receive advertisements through the app.
The app offers an optional Remove Ads annual subscription that removes ads. Family Sharing is included. All payments and subscription management are handled by Apple through the App Store.
The app does not collect or store any payment or credit card information. All transactions are processed securely by Apple.
Google and Apple may process data outside the European Economic Area (including in the United States). Where required, these transfers rely on appropriate safeguards provided by those companies (such as Standard Contractual Clauses) as described in their privacy documentation.
I do not store personal profiles myself. Data processed by AdMob, Firebase, or Apple is retained according to each provider’s retention policies for the purposes described above.
Calculus Doodlus is intended for a general audience. I do not knowingly collect personal information from children. Parents and guardians who have concerns about a child’s information should contact me. Advertising and analytics are subject to the consent and platform rules described above.
Because I do not operate user accounts or store personal profiles myself, there is no in‑app profile to modify or delete.
Where the GDPR applies, you may have the right to access, rectify, erase, restrict, or object to certain processing, and to data portability, as well as the right to withdraw consent at any time (without affecting processing based on consent before withdrawal). You may also lodge a complaint with a supervisory authority (in Germany, your state data protection authority or the Federal Commissioner for Data Protection and Freedom of Information).
For data processed by Google AdMob, Firebase, or Apple, please also use their privacy tools and policies. You can contact me at info@stephanbarbe.de for questions about this policy.
I may update this Privacy Policy from time to time to reflect changes in my practices or for other operational, legal, or regulatory reasons. I will post any changes on this page, and the “Last updated” date at the beginning of this document will indicate when the policy was last revised.
If you have any questions about this Privacy Policy, please contact me at:
info@stephanbarbe.de
These Terms of Use govern your use of Calculus Doodlus (“the app”). By using the app, you agree to these terms.
Calculus Doodlus is a handwritten calculation editor: you write calculations step by step on a tape, and the app evaluates them automatically.
The app offers an optional Remove Ads annual subscription:
Payment will be charged to your Apple ID account at confirmation of purchase.
The subscription automatically renews unless auto‑renew is turned off at least 24 hours before the end of the current period. Your account will be charged for renewal within 24 hours prior to the end of the current period at the cost of the renewal.
You can manage your subscription and turn off auto‑renewal in your Apple ID account settings after purchase (Settings → [your name] → Subscriptions), or as otherwise provided by Apple.
Payments are processed by Apple through the App Store. Subscription terms are also subject to Apple’s Licensed Application End User License Agreement (Standard EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Refunds are handled exclusively by Apple in accordance with their policies. The developer cannot process refunds directly.
You agree not to:
The app is provided “as is”, without any warranty of any kind, either express or implied. We do not guarantee uninterrupted or error‑free operation of the app.
We may update these Terms of Use from time to time. Continued use of the app after changes are published means you accept the updated terms.
For any questions regarding these Terms of Use, you can contact:
info@stephanbarbe.de