Privacy Policy

Reingewinn is a Shopify app that calculates profit per order and net profit per day. This policy describes which data the app processes. The German version (Datenschutzerklärung) is authoritative.

1. Controller

Malte Böhm Online Marketing, Malte-Fabian Böhm, Lehrer-Lohmann-Weg 4a, 21217 Seevetal, Germany. Phone: +49 151 70031149. Email: kontakt@malte-boehm.dev

2. Data Reingewinn processes

After a merchant installs the app, Reingewinn reads through the Shopify API:

• Order data without customer data: order number and date, amounts, taxes, discounts, shipping, refunds, payment gateways and line items (product, variant, SKU, quantity, price). Optionally the shipping country code, never an address.
• Product and variant data including cost prices.
• Shop settings such as currency, time zone and Shopify plan.

Reingewinn does not read or store names, email addresses, phone numbers or addresses of the shop's customers. In addition it stores what the merchant enters (costs, fees, ad spend) and the access credentials of the installation. If the merchant orders the weekly email report, Reingewinn also stores the email address the merchant enters for it (section 3a).

3. Connected ad accounts (Google Ads, Meta, TikTok)

When a merchant connects a Google Ads, Meta or TikTok ad account, Reingewinn only reads data (Google: the "Google Ads" scope, Meta: "ads_read", TikTok: account and reporting data). It reads the list of ad accounts with name, account ID and currency, and ad spend per day and campaign. Reingewinn never changes campaigns or accounts. Access tokens are stored encrypted (AES-256-GCM). The merchant can disconnect at any time in the app or revoke access in their Google, Meta or TikTok account.

Reingewinn's use and transfer of information received from Google APIs to any other app will adhere to the Google API Services User Data Policy, including the Limited Use requirements. Data from Google, Meta and TikTok accounts is used only to calculate the profit of the shop that connected it. It is not sold, not used for advertising and not shared with third parties.

3a. Weekly email report

The merchant can order a weekly report by email in the app's settings. For this, Reingewinn processes:

• the email address the merchant enters for it (stored encrypted, AES-256-GCM) and the language of the emails;
• the times of the request, the confirmation and the unsubscription, and the version of the consent text;
• per week the status and error code of the delivery, without the content of the email;
• the confirmation and unsubscribe links only as a hash; the links themselves only contain a random identifier, no email address;
• to prevent abuse, for each confirmation email the time and a value derived with a secret key (HMAC) from which the address cannot be recovered. This data is deleted after two days.

Purpose: sending the confirmation email and, every Monday, a report with the shop's key figures (revenue, profit, margin, orders, ad spend, product names with key figures).

Legal basis: consent (Art. 6(1)(a) GDPR), given in the app and confirmed via the confirmation link (double opt-in). The merchant can withdraw consent at any time with effect for the future: via the unsubscribe link in every email (open the link, then click “Unsubscribe”; in supporting email apps also directly via their unsubscribe button), in the app or by email to kontakt@malte-boehm.dev. Withdrawal does not affect the lawfulness of processing before the withdrawal (Art. 7(3) GDPR). Reingewinn keeps the times and the version of the consent text, also after a withdrawal, as proof of consent (Art. 7(1), Art. 5(2) GDPR; legal basis Art. 6(1)(c) GDPR, alternatively Art. 6(1)(f) GDPR with the legitimate interest of being able to demonstrate consent). The log with the derived value serves to prevent abuse and is based on the legitimate interest in protecting addresses from unwanted confirmation emails (Art. 6(1)(f) GDPR). Reingewinn keeps the details for each week (status, error code, time of sending, hash of the unsubscribe link) also after a withdrawal, to be able to demonstrate which reports were sent with consent and to keep recognising unsubscribe links from older emails (legitimate interest, Art. 6(1)(f) GDPR).

Retention: the address is deleted immediately when the merchant unsubscribes or uninstalls the app; unconfirmed addresses after 48 hours. The times and the version of the consent text of the most recent order are kept as proof until all data of the shop is deleted (section 6); if the merchant orders the report again, the new times and the new version replace the previous ones. The details for each week are kept, also after a withdrawal and alongside those of a later order, until all data of the shop is deleted (section 6). Backups are handled as described in section 6.

Delivery: the emails are sent encrypted (TLS) to the email provider (section 5); further delivery and storage are up to the recipient's mailbox. The emails contain no tracking pixels and no tracked links.

4. Purpose and legal basis

Processing is necessary to provide the app to the merchant (Art. 6(1)(b) GDPR). Error reports and load-time measurements (section 8) are analysed to keep the service secure, stable and fast (Art. 6(1)(f) GDPR). Where Reingewinn processes personal data on behalf of the merchant, it does so on the merchant's instructions (Art. 28 GDPR). The weekly email report is based on the merchant's consent (Art. 6(1)(a) GDPR, section 3a).

5. Recipients and service providers

• Hosting: Hetzner Online GmbH, Gunzenhausen, servers in Germany.
• Email delivery: ALL-INKL.COM – Neue Medien Münnich, owner René Münnich, Hauptstraße 68, 02742 Friedersdorf, Germany, as processor (Art. 28 GDPR).
• Error reports: a self-hosted GlitchTip server, receiving technical error details (message, code location, requested address without query parameters, browser and system version, and for errors in the app the shop domain and, where relevant, the ad account ID), no IP addresses.
• Shopify, Google, Meta and TikTok are the sources of the data; the exchange happens because the merchant installs the app or connects an ad account. Their own privacy policies apply.

6. Retention

Data is kept while the app is installed. 48 hours after uninstalling, Shopify sends a deletion request and Reingewinn deletes all data of the shop. The address for the weekly report is deleted as soon as the report is unsubscribed or the app is uninstalled (section 3a). Disconnecting an ad account deletes its access token; ad spend already fetched stays until the shop's data is deleted or the merchant deletes it. Error reports (section 5) are deleted automatically by GlitchTip after 90 days, even if the shop's other data was deleted earlier.

The database is backed up daily on the app's server, and also before every change to the database structure (migration). Deleted data may remain in a backup until that backup is deleted: daily backups after about two weeks (the last 14 are kept), backups taken before migrations only after five further migration runs. In addition, the provider copies the backups to its own computer and encrypts them before they are stored there; only the provider holds the key. These copies are deleted after about two weeks, the next time the computer fetches backups. If the server fails or the app moves (to a new server or to a newly created app), the latest copies are kept longer, until the app is making backups regularly again (for about one week after a move). Backups are only used to restore data after a failure or when the app moves, and to test that restoring works.

7. Cookies and tracking

Reingewinn uses no tracking or advertising cookies and no analytics services. Inside the Shopify admin only technically necessary session data is used. At times the app also measures its load time there (section 8).

8. Visiting this website

When you open this website, the server processes technically necessary connection data such as IP address, time, requested page and browser details to deliver the page and keep the service secure (Art. 6(1)(f) GDPR). The app's server log contains no IP addresses and no browser details, but technical details of the request such as the requested address, status code and response time, plus messages from the app such as error messages with the domain of the shop concerned. At times it also contains load-time measurements taken when the app is opened in the Shopify admin: how quickly the page appears and responds to input and how much the layout shifts, with the type, position and size of the affected page elements, no content, likewise with the shop domain. For this the app only reads page-load timings, the type of the largest page element and the type, position and size of shifted page elements in the browser and stores nothing on the device. The log is used for troubleshooting and to improve load time and is deleted with every update of the app. The public pages of this website (product, pricing, about & contact, legal texts and the pages to confirm or unsubscribe from the weekly report) load no content from third-party servers; if an error occurs, an error report may be sent to the self-hosted GlitchTip server (section 5).

9. Data security

• Transfer: All connections to the app and to the APIs of Shopify, Google, Meta and TikTok are encrypted with HTTPS (TLS). The server redirects HTTP requests to HTTPS.
• Storage: The database and its backups (including ad data retrieved from Google Ads, Meta and TikTok) are kept on an encrypted disk (LUKS2, AES-XTS with a 512-bit key) on the server in Germany. The copies of the backups on the provider's computer (section 6) are encrypted with age (X25519, ChaCha20-Poly1305) before they are stored; only the provider holds the key.
• Ad account OAuth tokens (for Google, the refresh token): They are additionally encrypted individually (AES-256-GCM). The key is derived from a secret set in the app's server environment; it is not stored in the database.
• Access: Only the provider can log in to the server; the data centre is operated by Hetzner (section 5). SSH login is possible only with a key; SSH password logins are disabled. Reingewinn checks requests from the Shopify admin and from Shopify with Shopify's session tokens and signatures (HMAC), so each shop sees only its own data. The return from the Google, Meta or TikTok login is bound to the shop by a signed parameter valid for 30 minutes.
• Data minimisation: For ad accounts Reingewinn uses read access only. It does not store customer data of the shop (section 2). Error reports and the app's server log contain no IP addresses.

10. Your rights

You have the right of access, rectification, erasure, restriction, data portability and objection. Contact kontakt@malte-boehm.dev. You may also lodge a complaint with a data protection supervisory authority, for example where you live or work. The authority responsible for the provider is the State Commissioner for Data Protection of Lower Saxony (Der Landesbeauftragte für den Datenschutz Niedersachsen), Prinzenstraße 5, 30159 Hannover.

Right to object: Under Art. 21 GDPR, you may object at any time, on grounds relating to your particular situation, to processing based on Art. 6(1)(f) GDPR (sections 3a, 4 and 8). An email to kontakt@malte-boehm.dev is sufficient.

Last updated: 31 October 2026