CiviCRM - A Constituent relationship management for the Civic Sector
EasyCall Phone Call Center - Instantly provide voice customer support through phone calls.
Odoo CRM - Open Source CRM
CloudTalk - Work locally, grow globally
Salesforce - CRM software solutions and enterprise cloud computing from salesforce.com, the leader in CRM and platform as a service.
CallKite - Your website’s video call center in just one click.