A privacy-first Android contacts app. Your contacts are encrypted end-to-end and stored on Nostr relays — readable only with your key, syncable across devices, with no central server.
Early work in progress.
| Contacts | Contact details | Add a contact |
|---|---|---|
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 |
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| Nostr-aware contacts | Nostr profile search |
|---|---|
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 |
- Encrypted everywhere — each contact is a NIP-44-encrypted
kind:30078event, replicated to every relay you enable. Encrypted at rest on-device too (Android Keystore). - System integration — contacts sync into Android's contacts provider, so they show up in the Phone, Messaging, and Mail apps.
- Relay management — add/remove relays, mark them paid/self-hosted, and detect a local relay (e.g. Citrine) for durable on-device backup.
- Nostr-aware — search profiles by name, show avatars, verify NIP-05, highlight linked contacts, pin favorites.
- vCard import/export and sign-in with a local key (nsec) or an external signer (Amber/NIP-55).
Requires Android Studio with a recent AGP/Kotlin toolchain. Builds are production-only — the debug
variant is disabled, so assemble/install always target the signed release build.
./gradlew assembleReleaseRelease signing is read from the HESSIBLE_KEYSTORE_FILE, HESSIBLE_KEYSTORE_PASSWORD,
HESSIBLE_KEY_ALIAS, and HESSIBLE_KEY_PASSWORD environment variables (the same ones CI uses).
GitHub Actions runs lint, unit tests, and a release build for pushes and pull requests. A
SemVer tag matching v* creates a native GitHub release from a commit already merged into main,
using the curated notes in RELEASE_NOTES.md. Release tags require these repository secrets:
HESSIBLE_KEYSTORE_BASE64HESSIBLE_KEYSTORE_PASSWORDHESSIBLE_KEY_ALIASHESSIBLE_KEY_PASSWORD
The release job verifies the APK package, version, and signing certificate before publishing it.
Release signing certificate SHA-256:
EC:82:BE:84:EA:62:1F:01:4B:9E:DE:7E:E5:B6:AF:D2:3B:03:95:EF:1C:FA:80:FE:3F:BE:39:CA:88:B8:75:E2.
Editable artwork and Android, macOS, and Linux exports live in branding/icons. See the platform preview.
Apache License 2.0 — see LICENSE. Copyright © hermeticvm.