Nostr event signer for Android
About this app
Amber is a nostr event signer for Android. It allows users to keep their nsec segregated in a single, dedicated app. The goal of Amber is to have your smartphone act as a NIP-46 signing device without any need for servers or additional hardware. "Private keys should be exposed to as few systems as possible as each system adds to the attack surface," as the rationale of said NIP states. In addition to native apps, Amber aims to support all current nostr web applications without requiring any extensions or web servers.
Licensed under MIT, by greenart7c3.
What's New in v6.2.3
Imported from the F-Droid repository index.
Version history
Jul 3, 2026 · 35.5 MB · Android API 26–37 · code 196
Imported from the F-Droid repository index.
SHA-256 48e97ccac4242328a9d709b3cae83578d338644f28ded3097b7a247601c7a563
Jun 21, 2026 · 37.1 MB · Android API 26–37 · code 195
Imported from the F-Droid repository index.
SHA-256 59b9ebbde625e13f4b0adcff8dc30d945dacab24a60a36b5f6aed3177bda1474
Jun 14, 2026 · 37.1 MB · Android API 26–37 · code 194
Imported from the F-Droid repository index.
SHA-256 1028678ace7fba7ad79b0633922ce0ede6d617dd7a3727b3e313f329a1245f4f
Will it run on your device?
92%
- Runs on a broad range of modern Android versions.
- Multiple CPU architectures are covered.
- Aligned with the latest Android target SDK expectations.
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 com.greenart7c3.nostrsigner 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, 6.2.2 is the last build before it. Android will not install an older version code over a newer one, so you must uninstall Amber 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 Amber, and a listing is removed when the evidence for it stops holding up.
Get Amber
Every source we list for com.greenart7c3.nostrsigner 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
48e97ccac4242328a9d709b3cae83578d338644f28ded3097b7a247601c7a563
Signing certificate
56dc631996a55c2284790448c7dc9f1dd05df596b2ce4882313633f5602e5fe4
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.