Privacy policy

Last updated: November 2026

This is a translation for your convenience. The German version is legally binding; you find it with the DE button at the top.

1. Controller

The controller for personal data processed on this website, in the Quershare app and on the license server is:

Yannick Papenfuß IT-Service
Owner: Yannick Papenfuß
Kaiserin-Augusta-Allee 34 A
10589 Berlin
Germany
kontakt@y-pp.de

I have not appointed a data protection officer, as I am not required to. For any privacy question, just write to the address above.

2. In short

Quershare needs no account. Your files and clipboard go directly and encrypted from device to device on your local network. I never see them.
The app contains no ads and no analytics or tracking tools, and sends no usage reports. I only get crash and error reports when you report a problem yourself – after you agree, and with content you see first.
The app only talks to my license server when you activate, buy or use Quershare Infinite. It then sends the license key, a random device ID and the device name.
When you buy on the website, Paddle is the seller; Paddle gives me your email address so I can send you the license key. When you buy on Google Play or in the App Store, I get neither your name nor your email address.
On your local network, the app shows itself under a random name that changes. Only members of your groups learn which device it is.
This website sets no cookies and loads no third-party content.

3. This website

Server log files

When you visit this website, the web server automatically records: IP address, date and time, the page requested, the amount of data sent, status code, referrer URL, and browser and operating system (user agent).

The purpose is to run the website securely and reliably, for instance to detect attacks. The legal basis is my legitimate interest in this (Art. 6 (1) (f) GDPR). The log files are deleted after 14 days, unless an entry is needed longer to investigate a specific incident.

Hosting

This website runs on a server that I operate myself. The server and data centre are provided by netcup GmbH, Daimlerstraße 25, 76185 Karlsruhe, Germany, under a data processing agreement according to Art. 28 GDPR.

No cookies, no third-party content

This website uses no cookies or similar technologies, no tracking and no analytics. Fonts and graphics are served from this server; visiting it sends no data to third parties (nor does the check in the report form, section 6). Only when you click "Buy Quershare Infinite" are you forwarded through the license server (section 5) to Paddle's checkout (section 7).

4. The app

Data on your device

The app stores settings, groups, the device list, history and received files on your device only. Your groups' keys are kept in the operating system's keychain (the macOS and iOS Keychain, Windows Credential Manager, Secret Service on Linux) or, where there is none, in a file only your user account can read. A group's password itself is not stored. None of this is sent to me.

On your local network

So that your devices can find each other, the app announces itself on the local network via mDNS (on iPhone and iPad through Bonjour). It does so under a random name that changes at every start, on every new network and after a day at the latest, and so does the certificate of its encrypted connections. The announcement contains neither your groups nor your device name nor any lasting identifier, so your device can't be recognized by it.

Which groups two devices have in common, they check with a method (CPace) that tells a device without a group's password nothing. Only then do members of a shared group exchange, encrypted with its key, the device ID, the device name and the kind of device (phone, tablet or computer, the operating system, and whether it is the App Store version; no model and no version numbers). Everything else – names of shared files, file contents, clipboard – only goes to members of your groups, encrypted with the group's key and over an encrypted connection (QUIC/TLS). No server is involved.

If you turn on "Visible to everyone", devices with Quershare near you see your device name, the device ID and the kind of device without sharing a group, and can send you things; you decide each time whether to accept. They don't see your shared files.

You are responsible for what you share and for whom you share a group with. I have no access to any of it.

Camera, NFC and notifications (Android, iPhone and iPad)

The app only uses the camera while you scan an invite QR code; the image is analysed on the device and neither stored nor sent. NFC is only used on Android, to pass an invite to another phone. Notifications show incoming files.

Log and crash records

The app keeps a log of what it does (for instance which devices it found and which connections failed) and records crashes. Both stay on your device, in the app's log folder; the log takes at most 10 MB, older entries are overwritten, and the last five crashes are kept. Nothing of it is sent unless you report a problem (section 6).

No analytics, no ads

The app contains no analytics, tracking or advertising libraries and sends no usage reports.

5. License server

For Quershare Infinite I run a license server (api.quersha.re; license.y-pp.de for older versions of the app). The app only connects to it:

to activate a license key or a purchase on Google Play or in the App Store,
to renew the license, at most once a week while Infinite is active and the device is online,
to remove the license from a device,
when you choose "Buy Quershare Infinite": the server forwards your browser to the checkout.

The license server processes:

the license key or the device's signed license,
the device ID (a random identifier the app creates when installed) and the device name, which you see and can change in the app,
the time of activation and of the last renewal,
your IP address, for technical reasons; it only ends up in the web server's log files (section 3) and is not stored with the license.

The purpose is to perform the license agreement: to unlock Infinite, to keep to the limit of 5 devices per license, and to revoke refunded or misused licenses. The legal basis is Art. 6 (1) (b) GDPR.

A device's link to the license is deleted when you remove the device in the app. The license itself (key, email address for website purchases, purchase ID, status) is kept as long as it is valid, so you can activate it again at any time. On request I delete it; Infinite can then no longer be activated. Revoked licenses are listed by their ID in a revocation list that is built into future versions of the app; it contains no other data.

The license server runs on the same self-operated server at netcup (see section 3).

6. Reporting a problem

With the report form you can tell me about a problem with Quershare. You reach it on this website, in the app under "Report a problem", or after a crash, when the app asks at its next start.

Diagnostic data from the app

When you open the form from the app, it first shows you what it would send, and only sends it if you agree. You can also send the report without this data. The diagnostic data contains:

the app's version, the operating system and its version, the processor architecture, on Linux the desktop environment, on phones the model,
the number of your groups and of the devices in them, each only with its kind (e.g. "Android phone") and whether it is reachable,
your settings as switches (e.g. whether notifications are on), whether Infinite is active,
your networks as subnets (e.g. "wlan0 192.168.1.0/24"), not your device's address,
recorded crashes (error message, place in the program) and failed starts,
the last part of the log (up to 1 MB).

Before the data leaves the device, the app replaces the names of your groups and devices with placeholders, shortens file paths to the kind of file (e.g. "<path>.pdf"), and removes keys, invite and license links, and email addresses. What can't be recognized this way may remain in the log; that's why you see the full content before sending.

The app uploads the data to the license server (api.quersha.re) and opens the form with a random ID. The data stays there until you send the report, a day at most; if you don't send the form or take the data out of it, it is deleted. Your IP address is stored with it, so that not too much data can be uploaded from one address; it is deleted with the data and not included in the report.

The form

In the form you enter a description, if you like an email address for questions, and a file (e.g. the log, when the app doesn't start). Against automated reports the form uses Cap, a check that runs on this server: your browser solves a small computing task and checks whether a person is using it. No data goes to third parties, no cookies are set, and the results of the check are not stored. I use your IP address to refuse too many reports from one address; it is only kept in memory for an hour and not stored with the report.

What happens with the report

The report – description, email address, language, diagnostic data and file – is stored as an entry in my issue tracker (Gitea, on my own server at netcup, see section 3), which only I can see. Reports of the same crash are grouped.

The purpose is to find and fix errors in Quershare and to answer you if needed. The legal basis is your consent (Art. 6 (1) (a) GDPR), which you give by sending the report; you can withdraw it at any time by email, and I then delete your report. I delete attached files and diagnostic data 90 days after the problem is resolved, the report itself when it is no longer needed for development.

7. Buying on the website (Paddle)

Purchases on this website are handled by Paddle.com Market Limited, Judd House, 18–29 Mora Street, London EC1V 8BT, United Kingdom ("Paddle"), as reseller (Merchant of Record). Your purchase contract is with Paddle. Paddle processes your payment, billing and contact details as an independent controller; see Paddle's privacy policy.

After your purchase, Paddle notifies me with the IDs of the purchase and of the customer, which I use to retrieve your email address. I store the email address and the purchase ID with the license, to send you the license key, to help with questions, and to revoke the license after a refund or chargeback. I receive no payment details. The legal basis is Art. 6 (1) (b) GDPR. The United Kingdom is covered by an adequacy decision of the EU Commission.

8. Buying on Google Play

In the Android app from the Play Store you buy Infinite through Google Play. The seller and controller for the payment is Google (in Europe: Google Ireland Limited, Gordon House, Barrow Street, Dublin 4, Ireland); see Google's privacy policy.

After the purchase, the app sends the Google Play purchase token to my license server. The server checks it with the Google Play Developer API and receives the purchase's status and ID, but not your name or email address. The token is stored with the license, so that the purchase maps to the same license after a reinstall, and to detect refunded purchases. The legal basis is Art. 6 (1) (b) GDPR.

9. Buying in the App Store

In the app from Apple's App Store you buy Infinite in the App Store. The seller and controller for the payment is Apple (in Europe: Apple Distribution International Ltd., Hollyhill Industrial Estate, Hollyhill, Cork, Ireland); see Apple's privacy policy.

After the purchase, when you restore a purchase, and at the app's first start on a new device, the app asks the App Store on your device whether your Apple Account bought Infinite. Only if it did, it sends the transaction signed by Apple to my license server. The server checks Apple's signature itself, without contacting Apple, and receives the purchase's ID, the product and the purchase date, but not your name, your email address or your Apple Account. The purchase's original ID is stored with the license, so that all your devices with the same Apple Account get the same license. The legal basis is Art. 6 (1) (b) GDPR.

10. Email

I send you the license key by email through my own mail server, which I also operate myself at netcup (section 3). Emails you send me arrive on the same server.

When you write to me, I process your message and contact details to answer it (Art. 6 (1) (b) GDPR for questions about a purchase or license, otherwise (f)). I delete the correspondence once it is settled, unless statutory retention duties (such as § 147 of the German Fiscal Code for business letters) require otherwise.

11. Recipients and other countries

Your data only goes to the parties named above: netcup as processor, and Paddle, Google and Apple as independent controllers for the purchase. I do not transfer data to countries outside the EU myself, except for retrieving the email address from Paddle in the United Kingdom (adequacy decision). Paddle, Google and Apple may transfer data to other countries under their own privacy policies.

There is no automated decision-making or profiling.

12. Your rights

You have the right to

access your data (Art. 15 GDPR),
rectification (Art. 16 GDPR),
erasure (Art. 17 GDPR),
restriction of processing (Art. 18 GDPR),
data portability (Art. 20 GDPR),
object to processing based on legitimate interest (Art. 21 GDPR).

An email to the address in section 1 is enough. For information about your license, please include the license key or the email address you bought with.

You can also lodge a complaint with a data protection supervisory authority, for example the one responsible for me: Berliner Beauftragte für Datenschutz und Informationsfreiheit, Alt-Moabit 59–61, 10555 Berlin, Germany.

13. Changes

When the app or the processing changes, I update this policy. The version published here applies. See also the license terms.