PhoneFusion, Inc. offers comprehensive communication solutions, including business phone systems, voicemail services, and contact center management.

Tandem Transit LLC: IP-based voice service provider and business consulting firm since 2010.

California-based Zingaya offers innovative click-to-call services via an embedded widget, enabling VoIP calls without downloads.

Amplion: A leading healthcare tech provider, innovating in patient-care communication since 1979.

Flyp, Inc.: A US-based telecom firm offering high-quality, multi-number calling and texting solutions globally.

Techstars: ARM Labs Lagos2023

PressOne: A comprehensive voice communication platform offering VoIP and call management solutions.

Pinger: A US telecom provider offering free texts, calls, and voicemails via a cross-platform app.

IP Unity offers a carrier-grade platform for enhanced voice and telephony applications, ensuring cost-effective network services.

Telnexus, established in 2012, is a trusted VoIP and Internet carrier, providing sophisticated digital phone services and telecom solutions for small businesses.

VoIP Group: Developing and marketing advanced internet telephony software solutions.

Phoneplus: An Android app offering affordable global call services.

Gogii: A free mobile communication service for texting, talking, and sharing.

InterMetro Communications, Inc. provides VoIP services to carriers, companies, and end users.

Utah-based organization, Versatel Networks, provides VoIP gateway and telecom service solutions.

Y CombinatorS22

Devyce: A VoIP system for businesses, offering instant mobile numbers, analytics, and more.

Y CombinatorS14 (Summer 2014)

Zip Phone was a cross-platform WiFi calling app integrated with Android for free VoIP calls.

Anta Systems provides affordable, turn-key VoIP solutions, simplifying deployments for service providers and SMEs globally.

Shoreline Communications: Award-winning provider of integrated Voice-Over-IP solutions for enterprises.

Fuze, acquired by 8x8, offered a global cloud-based unified communications and collaboration platform for enterprises.

Boston-based eYak provides IP telephony services and voice application solutions since 1999.

Zenring offers a social networking app for global calls at local rates, visual voicemail, and browser-based voice/video messaging.