Google Voice is a telephony service that provides call forwarding and voicemail services, voice and text messaging, as well as U.S. and international call ter…

TeamWox is a business collaboration software.

Plivo (Plēvō) is a cloud-based communication platform as a service (CPaaS), CPaaS fuses communications apps with business workflows.

Bitrix24 is a free (for small businesses) social enterprise platform.

Twilio is a cloud communications platform as a service (PaaS).

Voximplant helps to embed audio and video communication into your apps.