Crmble - Easy peasy crm for Trello
Onesheet CRM - The Simple CRM for Google Sheets
Followup.cc - FollowUp for email is a lightweight productivity suite that keeps your conversations and tasks from slipping through the cracks. Set perfectly timed reminders that arrive at the top of your inbox, right when you need them.
Zoho CRM - Omnichannel CRM for Businesses of all sizes
Freshsales CRM - A full-fledged CRM for high-velocity sales teams.
HubSpot - Grow Better With HubSpot: Software that's powerful, not overpowering. Seamlessly connect your data, teams, and customers on one CRM platform that grows with your business.