Real-time interpreter earpiece for iOS. VoxBridge continuously listens to ambient foreign-language speech via the device microphone and translates it into your language through your headphones, powered by OpenAI's GPT-4o Realtime API.
Two people speaking different languages, each with their own phone + headphones running VoxBridge. The app picks up what the OTHER person says and translates it. You just hear the translation whispered in your ear.
- iOS 17.0+
- Xcode 16.0+
- OpenAI API key with Realtime API access
- Headphones (wired or Bluetooth)
- Clone the repository
- Generate the Xcode project (requires XcodeGen):
xcodegen generate
- Open
VoxBridge.xcodeprojin Xcode - Set your development team in Signing & Capabilities
- Build and run on a physical device (microphone required)
If you don't have XcodeGen, create a new Xcode project manually and drag the VoxBridge/ folder into it.
- SwiftUI app lifecycle with
@main - AVAudioEngine for capture and playback with real-time sample rate conversion (hardware rate to/from 24kHz PCM16 mono)
- URLSessionWebSocketTask for the OpenAI Realtime API connection
- Server-side VAD for always-on ambient listening (no push-to-talk)
- Keychain for secure API key storage
English, Spanish, French, German, Italian, Portuguese, Japanese, Mandarin Chinese, Korean, Arabic, Russian, Hindi, Dutch, Swedish, Turkish
Approximately $0.30/min while active (GPT-4o Realtime pricing: ~$0.06/min audio input + ~$0.24/min audio output).
VoxBridge only uses the microphone to listen for speech to translate. Audio is streamed to OpenAI's API for processing and is not stored locally. Your API key is stored in the iOS Keychain and never leaves your device except to authenticate with OpenAI.