Marketo - Marketo's powerful marketing automation software helps marketers master the art & science of digital marketing to engage customers and prospects.
Tragofone - White-label VoIP Softphone with WebRTC and Auto-provisioning
Ortto - Journeys made simple. Your customer data, messaging and analytics working together.
PhonerLite - PhonerLite enables your PC to use it for internet telephony (VoIP , Voice over IP, SIP).
ActiveCampaign - Integrated email marketing, marketing automation, and small business CRM. Send beautiful newsletters, setup behavioral based automations, and benefit from sales automation.
tSIP - tomeko.net/software: SIP client for Windows.