EspoCRM - EspoCRM is open source CRM (Customer Relationship Management) software that allows you to see, enter and evaluate all your company relationships regardless of the type.
CiviCRM - A Constituent relationship management for the Civic Sector
Salesforce - CRM software solutions and enterprise cloud computing from salesforce.com, the leader in CRM and platform as a service.
Odoo CRM - Open Source CRM
Zoho CRM - Omnichannel CRM for Businesses of all sizes
Pipedrive - Sales pipeline software that gets you organized. Helps you focus on the right deals, so easy to use that salespeople just love it. Great for small teams.