Privacy Policy

Privacy Policy

This policy is to inform visitors to this website and users of the 23 Equations app about what personal information is collected and how it is used.

If you choose to use the app or website, then you are agreeing the terms of this policy. We will not use or share any information other than as described in this policy.

Information Collection and Use


This website does not collect any personal information such as names, email addresses or phone numbers from you and it uses no tracking cookies of any kind.

Free part of the App

None of the free functions of the app collect data which is communicated outside of your device in any way whatsoever. Some data is stored on your phone to let you know how you are progressing. This data never leaves your device and is deleted when your app is uninstalled. As part of running their app stores, Apple, Google or Microsoft collect some data which is made available to developers to to provide an overview of app usage.

Your School section of the App

Your school can choose to use the Your School section of the app. This allows them to set tests for you to help with revision. This means that some data is stored on our servers to allow teachers to see your answers. To prevent anyone but your teachers identifying you, two methods are used: your email is one-way encrypted so it cannot be read by anyone and your name is encrypted using a key known only to your teachers (and we encrypt it again before it is stored, just to make sure).

Individual users & 23 Extra section of the App

No data is collected that can in any way be linked to an individual. Purchases can only be made through the app store, no email address is collected or used and no names are requested. General usage patterns and test results may be collated and analysed to use to improve the app but will never be used in a way that the individual can be identified.

Use of your data

Your test results in the Your School section will be visible to your teachers once you upload them by syncing. Teachers can use this to give feedback and help them plan for future lessons. The teacher in charge has complete control over who can see your data. The developers may use anonymised statistics from the test answers to help identifying things like which equations students find more difficult, equations that may need more questions and better ways to pick the next question to ask. Generalised advice based on this analysis may be published on this website or via twitter with the aim of helping to improve students learning.

Use of Microsoft, Google and Apple OpenId Login data

The app now allows sign in without needing a pin code if your school email is provided by Google, Apple or Microsoft. As part of the login process, you will be sent to a web page in order to authenticate yourself and give permission for 23 Equations to receive confirmation of your email address. No other data (for example, your name) will be requested and no data, including the email address or any tokens received, will be stored by us. The only use of data will consist of one-way encrypting your email to compare it against our copy of the encrypted version provided by your school. Once the verification is completed, no data received from above mentioned providers will be retained.

Personal Data obtained via purchases or correspondence

Purchases made as in-app purchases by individuals are completely anonymous. The Application Stores do not disclose any Personal Data to us and we do not make any attempt to identify you other than an anonymous Id to allow you to access your saved data.

Purchases, by Schools, of the Your School service, may lead to 23 Equations receiving Personal Data in the form of names, email addresses and job positions. We will only use this information to respond to correspondence, to notify you of changes to the service, to remind you of the contract period ending and in relation to compliance with UK GDPR.

We will not disclose any Personal Data to a third-party. We will on a regular basis, delete old and out of date correspondence that may contain Personal Data but is no longer needed.

On request, we will remove your correspondence and any records of the Personal Data, immediately.

Other sources of Personal Data

We will not seek out or purchase any lists or Personal Data for any purpose including marketing.


All data is securely stored. All services used to store Personal Data are protected by two-factor authentication and access is severely restricted.

Every effort has been made to protect your privacy, in particular by collecting the minimum information necessary. The best practices in terms of encryption, authentication and protection have been followed. However, any method of transmission may be subject to as yet undiscovered methods of attack. Therefore care should always be taken to reduce the possible harm that could result from information relating to the app.

Third-part Service Providers

This website is hosted on Ionos servers. They may log IP addresses of visitors but according to their policy not to use or disclose this information other than to maintain the service.

In addition to Ionos, Google Gmail services are also used for some correspondence. Their policies can be found here.

The Your School feature requires internet access to work. The database and server functions are hosted on Microsoft Azure UK based servers to ensure quality of service and high standards of security. The servers are further protected by an internet firewall provided by Cloudflare. Authentication emails are sent via Mailjet for improved reliability of delivery. All delivery tracking is turned off.

Links to other sites

There may be occasional links to other sites. If you click on a third-party link, you will be directed to that site. We do no operate these external sites, therefore, we strongly advise you to review the Privacy Policy of these websites. We have no control over, and assume no responsibility for the content, privacy policies, or practices of any third-party sites or services

Your Individual Rights under GDPR

UK General Data Protection Regulation (GDPR) provide you with rights in relation to your personal data.

These rights cover personal data collected about you by your school and by the 23Equations app.

It is important to be aware that data held by 23 Equations is designed to be the absolute minimum needed to allow your school to use the app for its intended purpose of supporting homework and revision.

This means you cannot be identified just from the data held. The only way to identify you is by using your email address to match with records in the database. No other identifiable data is accessible to us.

This also means that your school is best placed to fulfil your requests relating to these rights. They should therefore be your first point of contact to exercise your rights under these regulations.

  1. Right to be informed

    You have the right to be informed about any personal data collected about you.

    How this is applied:

    No data is collected from or about you unless you enter it into the app. This data consists solely of the answers you enter and some meta-data about timing and help given.

    The only exception to this is your name (or its abbreviation) and email address which is entered by your school.

    As detailed earlier in the privacy policy, this data may be used anonymously to extract summary information such as most popular equations or most difficult questions.

    If anything changes, you will be informed of this through the app or this privacy policy.

  2. Right to rectification

    You have the right to have any inaccurate personal data rectified.

    How this is applied:

    Subject to verification of identity and reasonable proof of the inaccuracy of the data, the database will be corrected where possible.

    Please note, your name will only be visible to members of staff in your school. Only the member of staff in charge of administering the app can correct your name if it has been entered incorrectly. There are more options under the right to erasure which may be relevant.

  3. Right to erasure

    You have the right to have your personal data erased. This is also known as the right to be forgotten.

    How this is applied:

    Subject to verification of identity, all references to your name, email and all data in your tests will be erased from the database. This erasure will spread to all copies of the data cached on staff members’ devices when they next connect to the server to sync data.

    Subject to verification of identity, all references to your name, email and all data in your tests will be erased from the database. This erasure will spread to all copies of the data cached on staff members’ devices when they next connect to the server to sync data. To ensure the deletion is completed across all remote device, all of your information on the database is replaced with blank records. When a device is synced, the blank entries overwrite any copies of the records cached on devices.

    For school accounts, please contact your school account admin first.

    For anonymous accounts (eg if you purchased as an individual) and other accounts if needed, you can obtain a pin which you can use to authenticate yourself when contacting 23equations ( Use the "Authenticate To Server" feature for this.

  4. Right to restriction

    You have the right to restrict the processing of your personal data.

    How this is applied:

    Subject to verification of identity, your information can be anonymously added to a list of individuals to be excluded from any analysis queries of data in the database.

    You can ask your school to remove you from a group to avoid your marks being used for analysis of that group.

  5. Right to data portability

    You have the right to obtain and reuse your personal data for your own purposes across different services.

    How this is applied:

    Subject to verification of identity, a copy of the data entries can be provided for you. This will consist of raw JSON output from the database. Currently, there is no known services that can meaningfully use this data but it would be possible to “flatten” this file into a spreadsheet style format.

  6. Right to object

    You have the right to object to the processing of your personal data.

    How this is applied:

    In addition to the connected rights mentioned above (right to erasure and right to restriction), you can also prevent any further processing of your data by refusing to complete any further tests in the app. Apart from the previously mentioned trends analysis, you data will not be used for anything, including marketing etc.

  7. Right to related to automatic decision making and profiling

    You have right related to decision made without human involvement.

    How this is applied:

    There are no decisions made automatically about you. There are automated helpers to provide hints for you when you answer questions. These are considered legally completely insignificant and therefore not covered by the regulations. However, you do of course have the right to make further queries about this process if you wish.

UK GDPR Compliance

Information Commissioner's Office

Our ICO registration number is ZB538434.

How data is protected

A detailed assessment of what and why Personal Data is collected data and how that data is protected is available in the Data Protection Impact Assessment.

There is a less technical explanation of how the Secure-Key protects students' identity Data Protection Impact Assessment.

Data Processor Agreement

Schools that purchase access to Your School services are Data Controller for the Personal Data of their students and staff. This Data Processor Agreement [Link to follow] is the suggested contract, in accordance with Section 28 of UK GDPR, between the Data Controller (the School) and the Data Processor (23 Equations).


Children's Privacy

This app is designed to help student who are working towards their GCSE Science exams. The target age for this app is therefore ages 14-16. It is not targeted at children under the age of 13. However, it is clearly possible that children younger than the target age could be interested in the app. We do not collect personal identifiable information in the free section of the app. Only data entered by teachers is collected for the Your School feature. If you are a parent or guardian and have any concerns about this, please contact us so that we can help and if necessary, take actions.

Changes to This Privacy Policy

We may update our Privacy Policy from time to time. Thus, we advise you to review this page periodically for any changes. We will notify you of any changes by posting the new Privacy Policy on this page. These changes are effective immediately, after they are posted on this page.

Contact Us

If you have any questions or suggestions about our Privacy Policy, do not hesitate to contact us.