Privacy Policy

Last updated: October 14, 2026

1. Who we are

Feishu Digital, Grootsruhe 3, 20537 Hamburg, Germany. Email: feishudigital@gmail.com.

2. Our products

Feishu Digital builds browser extensions and web applications, including:

• Arztrechnung Prüfer — Free web app for checking medical bills (GOÄ/GOZ)
• Stationery Editor — Online editor for the printable stationery sold in our Etsy shop
• Digital Invitations — Interactive online invitations with RSVP and online greeting cards (weddings, parties, holidays), sold in our Etsy shop
• JVEG Rechner — Web app for JVEG compensation claims
• Readability Scorer — Chrome Extension for readability analysis
• AI Chat Organizer — Chrome Extension for organizing AI conversations

This list may change as we add or discontinue products.

3. Data we collect

Browser Extensions (Readability Scorer):

• All text analysis and data processing happens locally in your browser
• We do not transmit, store, or have access to your content
• Settings and preferences are stored locally using the browser’s storage API
• License key validation (Pro users) sends only the license key to the Lemon Squeezy API — no user content

AI Chat Organizer (Chrome Extension):

• The extension organizes your AI conversations by reading conversation titles and IDs from the platforms you use (ChatGPT, Claude, Gemini)
• To load your full conversation list, the extension uses the platform’s own internal API on your behalf (same-origin requests using your existing session — no credentials are shared with us or any third party)
• Conversation titles and IDs are cached locally on your device (via the browser’s storage API) so your organized folders persist across page reloads
• We never read, store, or transmit the content of your conversations — only titles and IDs are processed
• Your folders, tags, and settings are stored locally and synced via Chrome Sync (Google’s built-in browser sync)
• No data is sent to Feishu Digital servers. The only external call is license key validation via the Lemon Squeezy API

Static Web Apps (Arztrechnung Prüfer):

• All calculations and data processing happen entirely in your browser (client-side)
• No data is transmitted to any server
• Uploaded files (PDFs, images) are processed locally and never stored or sent

Stationery Editor (edit.feishudigital.de):

• Your wording is processed entirely in your browser. PDFs and images are created on your own device
• Your wording and choices are saved only in your browser’s local storage, so you can continue later on the same device. You can delete them at any time by clearing your browser data
• No wording or other content is transmitted to Feishu Digital or any third party. We do not use cookies, analytics or tracking
• Fonts and program files are served from our own host, not from external font or script services
• Hosted on Cloudflare Pages, which may collect basic server logs (IP address, browser type)

Digital Invitations (edit.feishudigital.de/einladung, invitation links /e/…):

For hosts who create an invitation or card (for example a couple, a party host or a family sending a holiday card):

• Before you publish, your draft is saved only in your browser’s local storage on your device
• To publish, you enter your Etsy order number and your email address. We check the order number with Etsy through Etsy’s API (for our own shop only) to confirm the purchase. We store the order number so that each order can be activated once; we do not store the other order details
• Your email address is used to send you login links and to identify your account. Login links are sent through Resend (see section 5)
• After you log in, we set one strictly necessary cookie that keeps you logged in for up to 90 days. We do not use cookies for analytics or advertising
• Your invitation or card (texts, design choices, the date of the occasion) and photos are stored on our server so that your guests can see them. Photos are made smaller in your browser before they are uploaded
• If you upload your own song, we store it on our server so it can play for your guests. You confirm that you have the right to use it. We remove songs when a rights holder notifies us
• If you add a guest list, we store the names and number of seats of each household (encrypted), so that guests can find their invitation by name or open a personal link
• You can invite other people (for example your partner or a co-host) by email to edit the invitation. We send them a login link and store their email address
• When guests reply, we email you a short summary at most once a day (only the number of new replies and how many guests are coming — no guest names or details). You can turn this off in the editor or with the link in each email
• If you protect the invitation with a password, we store only a one-way hash of it. Guests who enter it get a cookie that keeps the invitation open on their device for up to 180 days
• Your invitation, photos, music, guest list and account are deleted automatically 90 days after the date of the occasion you enter (for example the wedding, the party or Christmas Day; one year after activation if no date is set). You can ask us to delete them earlier at any time
• We keep only the Etsy order number and the activation date for three years, so that an order cannot be activated a second time. No other data is kept
• Legal basis: performance of our contract with you (Art. 6(1)(b) GDPR)

For guests who reply to an invitation or send a greeting back:

• Opening an invitation link does not require any personal data. If you reply, we store your name, whether you attend, which events you join, the number and names of the people coming with you, meal choices, a song wish, a note or greeting to the host and answers to the host’s own questions — whatever the host asks for and you fill in. On a greeting card, a greeting back contains only your name and your message
• If the host uses a guest list, you may be asked to type your name to find your invitation. We only compare it with the guest list and do not store what you type
• Allergies and dietary needs can be health data. They are only stored if you tick the consent box (Art. 9(2)(a) GDPR). Once saved, they are never shown again in a browser – only the host sees them. You can withdraw your consent at any time with “Delete my saved dietary information” when you change your reply, or by contacting us
• Your reply is stored encrypted (AES-256) and can only be viewed by the host who sent the invitation or card, after they log in. We do not use it for any other purpose
• All replies and greetings are deleted automatically 90 days after the date of the occasion, together with the invitation or card. The host can delete them earlier
• So that you can change your reply later, your browser keeps a copy of your reply and a key for it in local storage on your device. Clearing your browser data removes it
• Legal basis: handling the reply you send to the host (Art. 6(1)(b) and (f) GDPR); for allergies and dietary needs your consent (Art. 9(2)(a) GDPR)

For everyone:

• Invitation data, photos and replies are stored in a Cloudflare D1 database restricted to the EU (EU jurisdiction: stored and processed within the EU)
• To prevent abuse such as guessing order numbers or sending mass replies, we keep a one-way hash of your IP address for at most 24 hours. We do not store IP addresses in plain text
• When an invitation link is shared, apps such as WhatsApp may show a preview with the host’s names, the date and a picture of the envelope or gift box
• Hosted on Cloudflare, which may collect basic server logs (IP address, browser type)

Web Apps with Accounts (JVEG Rechner):

• Account data (email, name) for authentication
• Application data you enter (stored encrypted in the EU)
• No data is shared with third parties except for payment processing (Lemon Squeezy/Stripe)

This Website (feishudigital.de):

• Static site hosted on GitHub Pages
• We do not use cookies, analytics, tracking pixels, or third-party scripts
• GitHub Pages may collect basic server logs (IP address, browser type) — see GitHub Pages privacy

4. Payment processing

Payments are processed by Lemon Squeezy (Lemon Squeezy, LLC), who acts as Merchant of Record. Lemon Squeezy handles billing, taxes, VAT, and invoicing. We do not store credit card numbers or payment details. See Lemon Squeezy’s Privacy Policy.

5. Third-party services

• Lemon Squeezy — Payment processing and license management
• Supabase — Database and authentication for web apps (EU servers, Frankfurt)
• GitHub Pages — Static website hosting
• Cloudflare (Cloudflare, Inc.) — Web app hosting (Pages and Functions) and the database for Digital Invitations (D1, restricted to the EU)
• Resend (Resend, Inc., USA) — Sending login emails and reply summaries for Digital Invitations. Emails are sent from Resend’s EU region (Ireland); Resend may store sending records in the USA. Resend is certified under the EU-U.S. Data Privacy Framework and uses Standard Contractual Clauses
• Etsy (Etsy, Inc.) — Checking order numbers for Digital Invitations through Etsy’s API (our own shop only)
• Fly.io — Web application hosting (Frankfurt, Germany)
• Bunny Fonts — GDPR-compliant font delivery (no Google Fonts)

6. Your rights (GDPR/DSGVO)

As an EU resident, you have the right to:

• Access your personal data
• Rectify inaccurate data
• Request deletion of your data
• Object to processing or request restriction
• Data portability
• Lodge a complaint with a supervisory authority

To exercise any of these rights, email us at feishudigital@gmail.com.

7. Data storage and security

Browser extension data (settings, folders, tags, cached conversation titles) is stored locally on your device using the browser’s storage API and never transmitted to our servers. Web application data is stored on EU-based servers (Supabase, hosted in Frankfurt, Germany). Digital Invitations data is stored in a Cloudflare D1 database restricted to the EU; guests’ replies are additionally encrypted. We use encryption in transit (HTTPS/TLS) and at rest where applicable.

8. Changes to this policy

We may update this policy from time to time. Changes will be reflected on this page with an updated date. For material changes, we will notify affected users via email or product update.

9. Contact

Questions about privacy? Contact us at feishudigital@gmail.com.
Full contact details: see Impressum.