BreathState: A Cross Platform App for HRV Biofeedback and Resonance Breathing Protocols

Problem: Currently, resonance frequency-based HRV training is backed by robust scientific evidence, but it remains inaccessible to the masses due to the high costs of proprietary hardware and software tools. There is a need to bridge the gap between basic consumer wearables and professional open-source psychophysiological research. Solution: BreathState 2.0 solves this by evolving the existing mobile application into an active, multi-modal, clinical-grade biofeedback platform. This will be achieved by introducing cross-platform architecture (Mobile/Web/VR), integrating research-grade hardware (Vernier respiration belts), and porting Python-based professional analytics natively to the application. Deliverables: A multi-patient database architecture using Drift with CSV export capabilities. Cross-platform application builds supporting Android, iOS, and Web. Integration of Vernier GDX-RB respiration belts via BLE with Polar H10 synchronization. A full on-device NeuroKit2-to-Dart analytics engine (computing time-domain HRV, frequency-domain HRV, RSA, and Baevsky Stress Index). A real-time biofeedback dashboard featuring dual-axis waveforms and adaptive guided breathing. An immersive WebXR HRV visualization scene (breathing sphere) accessible via Meta Quest headsets.