hub.amSoftware by 3CLogic
8x8 Virtual Office - Use your iPhone, iPad or iPod touch to make and receive calls using your 8x8 Virtual Office phone...
Twilio - Brings voice and messaging to your web and mobile applications.
Vocalcom - Vocalcom is a cloud-based contact center, omni-channel customer experience and sales acceleration technology provider.
Nexmo - Nexmo is a simple two way SMS API with global reach and wholesale rates
CloudTalk - Work locally, grow globally
Plivo - Plivo simplifies your customer engagement.