Features

• Flutter UI with Windows, Linux, macOS, iOS, and Android support
• libp2p networking and cryptography, enables p2p networking without port forwarding
• Lossless raw audio and SEA codec options
• nnnoiseless noise suppression
• Built-in text chat with attachments
• Efficient use of CPU and memory resources
• Low end-to-end latency

Work in Progress

• Screensharing for Windows, macOS, and Linux
• Game overlay for Windows
• Web support
• Telepathy rooms (group calls)

Planned

• Lossless audio codec support
• QUIC datagrams for live audio streams
• p2p updates for desktop clients

History

• Began in 2023 as Audio Chat, a Python Tkinter app with simple UDP networking and AES cryptography
• Moved to the current Rust audio processing stack & Flutter UI for improved stability in 2024
• Soon after, the custom networking and cryptography stack was replaced with libp2p for improved security, p2p networking without port forwarding, and p2p networking in web browsers
• In 2025, performance improvements were made, SEA codec support was added, and many bugs were fixed

Architecture

High Level Design

• Flutter to Rust (and back) is enabled by Flutter Rust Bridge
• This design enables the same codebase to target desktop, mobile, and web

Audio Processing Stack

• Denoising runs on the sending side; each participant in a call decides if they want to use their compute resources to denoise their audio input
• When denoising is disabled, a custom output sample rate can be specified for network compatibility without the CPU overhead of noise suppression
• Every participant in a call must agree on the same audio codec options for sending & receiving
• If a frame's RMS is below the input sensitivity threshold, no audio is sent (keep-alive packets are used during silence)
• In a classic two-way call, each client runs a sending stack and a receiving stack
• In a Telepathy room, certain parts of each stack are duplicated to support more participants

UI Screenshots

Learn More

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