Aria vs Halcyon

Aria is a native SIP softphone for connecting to standards-compliant SIP servers. It handles inbound and outbound calls, mute, hold, transfers, DTMF, presence, contacts, and call history. Audio support includes Opus up to 48 kHz, G.711, an adaptive jitter buffer, and local WAV recording. Desktop downloads are available for macOS, Windows, and Linux, with signed installers and in-app updates. The maker says iOS and Android apps are in testing and have no releases yet. A self-hosted push gateway is required for mobile apps to receive incoming calls in the background. Aria names Asterisk, FreeSWITCH, and 3CX as compatible server examples and also works with the maker's AriaRoute hosted PBX. The privacy policy says it has no telemetry or analytics and stores credentials, contacts, call history, and recordings locally. SIP signalling can use TLS and media SRTP, but the maker says this is not end-to-end encryption. Aria is free for personal and non-commercial use; business use requires a separate commercial licence.

Halcyon is a free, pre-1.0 Android softphone built on PJSIP and integrated with Android Telecom. It registers with a PBX over UDP, TCP, or TLS, advertises RFC 8599 push parameters, and supports several SIP identities with an account selected for each call. When server-side push is configured, the registrar sends a data-only FCM message before an incoming INVITE to wake the device. Without push, Halcyon uses a foreground SIP service with permanent TLS registration and the associated battery cost. Its Android ConnectionService handles tel: and sip: calls, including from the lock screen, while Telecom-native routing supports Bluetooth headsets and Android Auto. Listed audio codecs are Opus, G.722, AMR-WB, and G.729; video codecs include VP8, VP9, and arm64 MediaCodec H.264. Media uses SRTP encryption, with ZRTP on the roadmap. Android 8.0 or newer is required; signed APKs are available from GitHub Releases.