BirdSong Messenger

BirdSong is a new kind of communication app that exchanges data with nearby devices using nothing but sound.

With no network connection required, it sends text and images using only your speaker and microphone. Even when the internet, Wi-Fi, Bluetooth, and cellular data are all unavailable, you can still communicate as long as your devices are within earshot.

■ Key Features

• Sound-based data transfer: encodes data into audio and sends it through the speaker, decodes it through the microphone
• End-to-end encryption: message content is encrypted with AES-256-GCM
• PIN-based channels: each device has a unique PIN, so messages reach only the intended recipient
• Reliable delivery: automatic retransmission (ARQ) keeps delivery reliable even in noisy environments
• Text/image messaging with history management

■ Who it's for

• Anyone who needs short-range communication where there's no network infrastructure, or the network can't be trusted
• Anyone who wants to be prepared for communication outages during disasters or emergencies
• Anyone curious about a new kind of short-range communication technology

※ For reliable transmission, both devices need to be within a distance where they can hear each other clearly (typically the distance of an indoor conversation). Transmission speed and success rate may vary in noisy environments.