Back to home

Privacy policy

What Dachsi stores, why, and how to delete it.

Last updated 5 November 2026

The short version

  • We use your data to run Dachsi and to see which parts of the app work.
  • We don't show our own ads, don't sell your data and don't track you across other apps or websites.
  • Videos play in YouTube's player, so Google receives what it needs to play them.
  • You can delete your account in the app at any time, and your data goes with it.

1. Who is responsible

The controller under the GDPR, for the Dachsi app and this website, is:

Alexander Salomon
Verganistrasse 16
3644 Emmersdorf, Austria
support@dachsi.app

2. What the Dachsi app stores

Your account
A random user ID, created the first time you open the app, so you can use Dachsi without signing in. If you choose to sign in with Apple, Google or an email code: your account ID with that provider and your email address. Apple may give us a private relay address instead.
Your profile
Your level, interests, daily goal, reminder time and app language, any other answers you give during onboarding, and a display name if you post on the feedback board.
Your learning
The words you save, your notes, your flashcard reviews and when each word is next due, the clips you saved, the clips you watched and how long you watched them, and your minutes per day.
Your subscription
Apple handles the payment, so we never see your card details. We and RevenueCat record your plan, whether it's active and when it renews or ends, linked to your user ID.
The feedback board
What you post, comment on and vote for, your reports and the users you block. Your display name, posts and comments are visible to other Dachsi users.
Reports and messages
Why you reported a clip. If you contact us: your topic, message and email address, with your app version, device model and user ID so we can help faster.
Usage statistics
Events such as which onboarding steps you reach, which clips you watch or skip, which words you tap or save, and purchases, with your user ID, app version, device model, system version, language and similar technical details. Your IP address is discarded and not stored. You can turn this off in Settings, under Share usage analytics.

These stay on your iPhone: the copy of your words that your widgets show, your scheduled reminders, and your playback and subtitle settings. Pronunciation uses your iPhone's built-in voice. The app also keeps your user ID and an analytics ID on your iPhone, to keep you signed in and to recognise your device between sessions.

3. YouTube

Dachsi uses YouTube API Services to find videos and to show them. Clips play in YouTube's official embedded player, and video thumbnails load from YouTube's servers.

When a clip or thumbnail loads, your iPhone connects directly to YouTube, which is part of Google. Google receives your IP address, technical details about your device, and which video is playing. YouTube may store or read cookies and similar technology on your device, and may show its own content, including ads, in the player. We don't control this and don't receive that data.

Dachsi never asks you to log in to YouTube and can't access your YouTube account, even if you sign in to Dachsi with Google. The list of clips you watched stays in our own database, as described above, and we don't send it to YouTube.

Google handles this data under the Google Privacy Policy. The player is covered by the YouTube Terms of Service.

4. Why, and on what legal basis

Running the app
Your account, learning data, subscription, the feedback board and playing clips, to provide the service you asked for. Art. 6(1)(b) GDPR (contract).
Usage statistics
To see which parts of Dachsi work, fix problems and test improvements, such as different onboarding steps. Art. 6(1)(f) GDPR (our legitimate interest). You can object at any time by turning off Share usage analytics in Settings.
Safety
Reports, blocks, filters and security logs, to keep Dachsi and the feedback board safe. Art. 6(1)(f) GDPR.
Support
To answer you when you write to us. Art. 6(1)(b) or (f) GDPR.
The waitlist
To tell you when Dachsi is out. Art. 6(1)(a) GDPR (your consent).

Your feed is ordered automatically from your level, your interests and what you've already seen. This has no legal or similarly significant effect on you.

We don't sell your data, we don't show our own ads, and we don't track you across other apps or websites.

5. Who processes it for us

These providers work for us under data processing agreements (Art. 28 GDPR) and have to protect your data to at least the standard of this policy. Where data leaves the EU, the transfer relies on the EU–US Data Privacy Framework or the EU's standard contractual clauses.

Supabase
Database, sign-in and server functions, hosted in Ireland.
RevenueCat
Subscription status, in the USA.
PostHog
Usage statistics and feature flags, hosted in the EU.
Resend
Sends sign-in codes, support messages and the launch email, from Ireland. The company is based in the USA.
Cloudflare
Hosts this website and routes email to our support address, on its worldwide network.

Apple (the App Store, payments and Sign in with Apple) and Google (YouTube, and Sign in with Google if you choose it) handle data as independent controllers, under the Apple Privacy Policy and the Google Privacy Policy.

6. How long we keep it, and deleting your account

We keep your data for as long as you have a Dachsi account. To delete it, open Settings in the app and choose Delete account. That removes your account, profile, words, notes, progress, saved clips, posts and comments, and your records at PostHog and RevenueCat. Copies in our hosting provider's backups are gone within 30 days. Apple keeps its own purchase records.

Deleting your account doesn't cancel an App Store subscription. Cancel it first, in your iPhone's Settings under your name, Subscriptions.

If you can't open the app any more, write to support@dachsi.app and we'll delete your data.

An account you never signed in to is deleted after 24 months without use. We keep support messages for up to 3 years. A waitlist address stays until you unsubscribe, and at most 12 months after the launch email.

7. This website

dachsi.app sets no cookies and uses no analytics or tracking. Fonts and images load from our own site.

Cloudflare hosts the site and keeps standard technical logs for a short time (IP address, browser and device type, requested page and time), for security and troubleshooting. We don't link them to anything else. Art. 6(1)(f) GDPR.

If you join the waitlist, we store your email address and the date, plus a tag if you came through one of our tagged links, for example from a TikTok video, so we can see which ones bring people. The list is stored at Supabase in Ireland. The launch email goes out through Resend and has an unsubscribe link.

If you use the support form, your topic, message and email address reach us by email, through Supabase, Resend and Cloudflare.

8. Your rights

You can ask us for access to your data (Art. 15 GDPR), correction (Art. 16), deletion (Art. 17), restriction of processing (Art. 18) and portability (Art. 20). You can object to processing based on legitimate interest (Art. 21), and withdraw your consent at any time with effect for the future.

Write to support@dachsi.app and we'll answer within one month. You can also complain to a supervisory authority. Ours is the Austrian Data Protection Authority (Datenschutzbehörde, Barichgasse 40–42, 1030 Vienna, dsb.gv.at).

9. Children

Dachsi isn't intended for children under 16, and we don't knowingly collect their data. If you think a child has given us data, write to us and we'll delete it.

10. Changes

If we change this policy, we'll update this page and the date at the top. We'll tell you in the app about significant changes.