VoAny

VoAny is an Android app for IMS calls and messaging. It uses Shizuku to perform AKA authentication with the selected SIM, establish an ePDG tunnel, and register with IMS.

Features

• Outgoing and incoming calls with Android Telecom integration.
• SMS over IMS, with messaging and contacts screens.
• SIM selection, connection status, and a background connection service.
• Selectable lwIP userspace or Android VPN backend, IPv4 / IPv6 support, and MOBIKE network migration.
• Advanced settings for ePDG, SMSC, and connection options.

Availability depends on the SIM and core network. Emergency calling is not supported.

Project Structure

• VoAnyApp: application UI and Android Telecom integration.
• VoAnyLib: SIM authentication, ePDG, IMS, SIP, messaging, and audio components.
• APP-ARCH.md: architecture and implementation details.

Building

Requirements: JDK 17, Android SDK 36, NDK 27.1.12297006, Git, and Python 3.9 or later. The current build supports arm64-v8a devices running Android 12 (API 31) or later.

Set the Android SDK path in local.properties, for example:

sdk.dir=C:/Users/your-name/AppData/Local/Android/Sdk

Gradle runs VoAnyLib/prepare-upstreams.py to fetch the pinned strongSwan and lwIP revisions from upstream.lock.json and apply the required project patch. The first build requires network access.

Prepare OpenSSL

OpenSSL static libraries and headers are excluded from version control and must be prepared for a fresh checkout. On Linux / WSL, install a Linux Android NDK and extract the OpenSSL 3.5.4 sources, then run these commands from the project root:

python3 VoAnyLib/prepare-upstreams.py
export ANDROID_NDK_ROOT=/path/to/android-ndk
export OPENSSL_SRC=/path/to/openssl-3.5.4
bash VoAnyLib/native/build-openssl.sh

The output is placed in VoAnyLib/src/main/jni/openssl. Windows builds can use these artifacts, but the OpenSSL build script requires Linux.

Build the App and Library

Windows PowerShell:

.\gradlew.bat :VoAnyApp:assembleDebug :VoAnyLib:assembleDebug
.\gradlew.bat :VoAnyLib:testDebugUnitTest :VoAnyApp:lintDebug

On Linux / macOS, use ./gradlew. Add -PvoanyPython=python3 if your Python command is python3. Once dependencies are cached, you can add --offline.

Outputs:

• APK: VoAnyApp/build/outputs/apk/debug/VoAnyApp-debug.apk
• AAR: VoAnyLib/build/outputs/aar/VoAnyLib-debug.aar

Usage

1. Install and start Shizuku, then open VoAny and grant Shizuku permission.
2. In Settings, tap Refresh SIMs, select the SIM to use, and grant microphone and notification permissions.
3. Ensure the selected SIM is not registered on a cellular network. You can use Phone Info in NetMonster: select the correct SIM and set its network mode to GSM Only or WCDMA Only, or turn off Mobile Radio Power. Available options vary by device.
4. GSM / WCDMA Only may still allow cellular registration. Confirm that VoAny shows Network: Unregistered and that the SIM remains accessible. Keep an internet connection available, such as Wi-Fi.
5. Tap Start service. The Android VPN backend requires VPN consent; the lwIP backend does not.
6. Wait for ePDG Connected, SIP Registered, and the green status indicator. Use DialPad to make calls, answer incoming calls, or use Messages for SMS.

VoAny connects only when the selected SIM is confirmed to be unregistered on WWAN. If it registers on a HOME or ROAMING network, the service stops immediately. After returning to an unregistered state, tap Start service again. Red indicates unavailable, yellow indicates connecting, and green indicates ready for calls.

Advanced settings is hidden by default and provides ePDG overrides, backend selection, IPv6 preferences, and a stop-service control. Stop the service before changing the SIM or backend. After testing, restore the original network mode and Mobile Radio Power setting in Phone Info.