RCQ Android

Android client for RCQ, an end-to-end encrypted messenger whose identity is a number the network issues you. No phone number, no email, no name, no ads. Censorship circumvention is built into the app rather than left to the user.

• Site and downloads: https://rcq.app
• Latest release: the releases page (rcq-universal.apk plus per-ABI builds; the same files are mirrored at https://rcq.app/android/ for networks where GitHub is throttled).
• Protocol spec: https://github.com/rcq-messenger/rcq-spec
• Reference server: https://github.com/rcq-messenger/rcq-server-ref
• iOS client: https://github.com/rcq-messenger/rcq-ios

Status: published. Distributed by sideloading and through our own F-Droid repository, with a Google Play build on its way. The sideload build self-updates from a manifest, trying dl.rcq.app/android/latest.json first and rcq.app/android/latest.json after it; the Play build updates through Play. Messages, groups, calls and media are cross-platform with the iOS and web clients.

What is in here

Path	What it is
app/src/main/java/app/rcq/android/crypto	libsignal-android integration, sealed sender, sender keys
app/src/main/java/app/rcq/android/net	REST + WebSocket client, and SingBoxTransport, the embedded circumvention transport
app/src/main/java/app/rcq/android/push	UnifiedPush connector, plus push/embedded: our own in-app UnifiedPush distributor
app/src/main/java/app/rcq/android/ui	Compose screens
app/src/main/java/app/rcq/android/nearby	Nearby, plus Radio Chat: the offline mesh over BLE + Wi-Fi Direct
app/src/main/java/app/rcq/android/backup	The .rcqbak archive: the same file the iOS and web clients read
app/libs/rcqbox.aar, tools/rcqbox/	The sing-box library behind SingBoxTransport, and the wrapper it is built from; tools/build-rcqbox.sh rebuilds it byte for byte
docs/	REPRODUCIBLE-BUILDS.md — how to check a published APK, and rcqbox.aar, against this source

Building

./gradlew :app:assembleDebug

Requirements: Android SDK 36, and a JDK. Any JDK 17 or newer builds a debug APK. Reproducing a published APK is a different question and needs the exact toolchain — JetBrains Runtime 21.0.9, the one bundled with Android Studio. See docs/REPRODUCIBLE-BUILDS.md; building a release on a different JDK will not match the signature you are trying to verify. Everything else is fetched by Gradle.

A release build reads keystore.properties from the repo root for signing. That file is gitignored and our release key is obviously not in here; without it the release variant falls back to the debug key.

Notes for anyone reading the code

• Push does not use FCM. Google services are unreachable in the target region, so wakes ride UnifiedPush. The app ships its own distributor (push/embedded) pointed at our own push server, and any third-party distributor such as ntfy stays selectable in Settings.
• Circumvention is in-process. sing-box runs inside the app and exposes a local SOCKS proxy. No system VPN profile, no second app to install.
• The server is replaceable. An account lives on the island its owner picked, and anyone can run one from rcq-server-ref.
• Radio Chat is a separate mode, not the transport. Normal messaging goes over the internet like any other messenger; the BLE + Wi-Fi Direct mesh is an extra for when there is no network at all.

License

GNU AGPL-3.0. A network-facing service built from this code must publish its modifications under the same license. Third-party attributions are in NOTICE.

Security

Please report vulnerabilities to [email protected] before filing a public issue. See SECURITY.md.