Companion App for the card10 Chaos Communication Camp badge.
About this app
The card10 can record an Electrocardiogram (ECG), comes with Bluetooth, MicroPython, colourful LEDs and a lot more. It will comfortably take place on your wrist and you can extend it with a needle and some (conductive) thread. It will help you to interact with others as well as the camp itself.
Licensed under MIT.
What's New in v0.9
Imported from the F-Droid repository index.
Version history
Dec 28, 2021 · 3.7 MB · Android API 21–29 · code 9
Imported from the F-Droid repository index.
SHA-256 6b0255c66feb01b5b79ff8f70deccd9fdd36383d24c10f985cc89cf72e050487
Dec 12, 2021 · 3.6 MB · Android API 21–29 · code 6
Imported from the F-Droid repository index.
SHA-256 0dabae692cf43f9a3f9fd7a4cb3479f45d4973cf6ab58756ee8fd06abfda642f
Aug 31, 2019 · 3.6 MB · Android API 21–29 · code 4
Imported from the F-Droid repository index.
SHA-256 ddaf41ac522539862a1eac483a7ca232d1a104b7aa014e5595cadf8a3146bd84
Will it run on your device?
73%
- Runs on a broad range of modern Android versions.
- ABI coverage is focused on newer 64-bit devices.
Installation Guide
Open Settings on your Android device
Go to Security → Unknown sources (or Install unknown apps)
Enable "Allow from this source" for your browser or file manager
Open the downloaded APK file from your Downloads folder
Tap "Install" and wait for installation to complete
Launch the app from your home screen
Make sure to re-enable Unknown Sources restrictions after installation for security.
How to install this safely
How to verify the file you downloaded
Before you install anything, confirm the file is the one described here. On a computer, run shasum -a 256 your-download.apk (macOS or Linux) or certutil -hashfile your-download.apk SHA256 (Windows), then compare the output character-for-character with the SHA-256 on this page. If a single character differs, the file is not the build we recorded — delete it.
What the signing certificate proves
Every Android app is signed with a private key that only its developer holds. The fingerprint on this page is a hash of the matching public certificate, and it proves continuity rather than identity: it tells you a build came from whoever signed the earlier ones. Android enforces this at install time — if a package claiming to be de.ccc.events.badge.card10 is signed with a different key, the system will refuse to install it over your existing copy. A fingerprint that changes between releases is worth pausing on, because a repackaged app that has been modified by someone else cannot keep the original signature.
How to roll back to an earlier version
If the current release misbehaves, 0.6 is the last build before it. Android will not install an older version code over a newer one, so you must uninstall card10 Companion first — which clears its local data unless you have a backup. Reinstall the older APK only if its signing fingerprint matches the build you already trust, and check the API range: an older release may target an Android version your device has moved past.
Why we list sources instead of hosting everything
The official store channel is almost always the right choice: it updates automatically and carries the publisher's own distribution guarantees. A direct APK is useful when a device has no store access, when a rollout has not reached your region, or when you need a specific version — and only when the publisher has authorized that copy. APKBrowse does not list pirated, cracked, or unauthorized rebuilds of card10 Companion, and a listing is removed when the evidence for it stops holding up.
Get card10 Companion
Every source we list for de.ccc.events.badge.card10 is legality-reviewed. Pirated or cracked builds are never offered.
Other sources
F-Droid listing
officialF-Droid builds this app from source and signs it. This is its official listing, with older builds and full release notes.
Source code
verified publisherThe upstream repository this build is compiled from.
We check legality and signature continuity, but device behaviour still varies. Install at your own discretion.
App Information
Security Verification
We record provenance; we do not run malware scans. Verify the hash yourself before installing.
SHA-256 Hash
6b0255c66feb01b5b79ff8f70deccd9fdd36383d24c10f985cc89cf72e050487
Signing certificate
c3f96fefd301177f295a1660b94d772c9600b84d8ecf6a63bf4bfb7867c4e106
Permissions Required
Previous Versions
The signing certificate fingerprint for this release is on record, so a build that does not match it did not come from this publisher.
Report a problem with this listing
A listing is only as good as its corrections. If a source is broken, a signature looks wrong, or this app should not be here, tell the moderation team.