Callab AI Alternative: The Mature Platform for Legacy PBX Voice AI
Callab AI (YC P25) validates what VoiceInfra has been saying: AI voice agents should work with your existing PBX, not force a cloud migration. Both platforms connect to legacy on-prem phone systems. But VoiceInfra brings an owned carrier network, 5+ LLM providers, MCP integration, and engineering support - capabilities a 7-person startup cannot yet deliver.
VoiceInfra vs Callab AI: Feature-by-Feature
A transparent comparison so you can make the right choice for your business.
Purpose-Built for Legacy PBX With Fast Deployment
Callab AI directly connects to Cisco UCM, Avaya, Mitel, and FreeSWITCH via SIP trunk - deployable in 1 week. They target the 58% of call centers still on on-prem infrastructure, with special strength in Arabic dialects. Their $240-600/month pricing is accessible for mid-market businesses. As a YC-backed company, they have strong product focus and are moving fast.
Early-Stage Startup With Limited Features and Scale
Callab AI is a 7-person YC P25 company - very early stage with limited production track record. No owned telephony network (dependent on your PBX/SIP infrastructure). LLM provider options are unclear. No MCP integration. No engineering support services (team is too small). Limited language support beyond Arabic, English, Turkish, and French. No no batch calling, no WhatsApp integration. Enterprise customers betting on Callab AI are betting on a very young company.
Why Teams Choose VoiceInfra Over Callab AI
VoiceInfra is built from the ground up for telecom operators, MSPs, and contact centers who need deep PBX integration.
Mature, Battle-Tested Platform
VoiceInfra serves production deployments today with carrier-grade infrastructure. Callab AI is a promising YC startup - but still building out their platform and team.
5+ LLM Providers With MCP Integration
Choose OpenAI, Anthropic, Google, Groq, or Mistral AI on any plan. Connect to any API via MCP. Callab AI's LLM and integration capabilities are still developing.
Owned Carrier Network
VoiceInfra operates its own SIP infrastructure with 100+ country codes. Callab AI connects to your PBX but relies on your existing telecom infrastructure.
Callab AI proves the market for legacy PBX voice AI is real. Choose VoiceInfra when you need a mature platform with carrier infrastructure, LLM flexibility, and engineering support - not a bet on an early-stage startup.
Contact SalesReady to switch?
See why businesses are choosing VoiceInfra over Callab AI. Contact our sales team for a platform walkthrough and see exactly how VoiceInfra handles what Callab AI cannot.