Next-Gen SIP / WebRTC
Hybrid Calling Platform
From app-to-app calls to PBX and PSTN. Automatically selects the optimal protocol to provide an ultra-clear, seamless calling experience.
Key Features of Tsuwa
Hybrid Smart Routing
Prioritizes P2P WebRTC for 1-on-1 calls. Automatically connects to SIP extensions and PSTN gateways without requiring manual protocol switching.
Group Calls & Voice Rooms
Powered by Anycast edge-managed SFU (Cloudflare Calls). Experience crystal-clear, low-latency group voice and video communication.
Multi-Platform Support
Unified calling experience across iOS (SwiftUI), Android (Jetpack Compose), and modern Web browsers with shared core logic.
Flexible Communications Architecture
WebRTC + SFU / TURN
Utilizes Opus, AV1, and VP9 codecs for internal and group calls. High reliability NAT traversal with coturn and resilient media relay via SFU.
SIP (Kamailio / BYOA)
Integrates with user-owned SIP servers (Bring Your Own Account) and Kamailio. Reliable incoming call delivery via tsilo and native Apple Push Notifications (APNs).