Privacy
Last updated: 2 November 2026
Who is responsible
ConcenTraining is made by Ambrus Kántor-Horváth in Hungary. For any question about your data, email concentrainer@gmail.com.
The short version
Your sessions, history and settings stay on your device. ConcenTraining has no accounts, no analytics, no advertising and no cookies.
What stays on your device
Your settings, the session that's running, your session history and the characters you create (their names and looks) are saved in your browser's storage on this device. They are never sent to us. You can delete single sessions on the History page, your characters with Delete on their cards, or everything by clearing this site's data in your browser settings. Export creates a file on your device; we never see it.
If you turn on "Remind me if I leave the app", your browser asks for permission to show notifications. These notifications are created on your device, and nothing about them is sent to a server.
What is sent to our server
When you tap Start session, the app sends the name of the character you chose (for example "grandma") to our server. If you chose a character you created, it only sends "custom": never its name or look. We keep only a count per character per day, to see which characters are popular. Nothing that identifies you is stored with it.
To stop anyone from inflating these counts, the server limits how many counts one IP address can send per minute. The IP address is used only for this limit and is not saved with the counts.
Hosting
The site is hosted by Netlify, Inc. in the USA. Like any web server, Netlify processes technical data for each request, such as your IP address, your browser type and the page you asked for, to deliver the site and keep it secure. Netlify does this on our behalf as a data processor, under its Data Processing Agreement. According to that agreement, its logs are kept online for 90 days and offline for up to 1 year, and data is transferred to the USA under the EU-U.S. Data Privacy Framework.
Why we may do this
The character counts and the hosting logs are based on our legitimate interest in running the site securely and knowing which characters people use (Article 6(1)(f) GDPR). Saving your data on your device is what makes the app work the way you asked.
Your rights
Under the GDPR you can ask to access, correct or delete your personal data, to restrict or object to its processing, and to receive it in a portable format. Because your history is only on your device, you can view, export and delete it yourself in the app. For anything else, email concentrainer@gmail.com. You can also complain to the Hungarian data protection authority, NAIH.
Changes
If this changes, for example when accounts or payments are added, this page will be updated before the change goes live.