Zoho CRM - Omnichannel CRM for Businesses of all sizes
Hiver - Manage Customer Support, Sales and Projects right from your Gmail inbox. Collaborate with Shared Labels, Shared Contacts, email notes, email reminders and email templates
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.
Clean Email - Clean Email is an online service that empowers you to take control of your mailbox.
Copper - Copper (formerly ProsperWorks) is easy-to-use customer relationship management for small businesses. Capture contacts and sales leads direct from Gmail with our simple CRM.
Nylas Mail - The Nylas Cloud API powers your application with email, calendar & contacts features. Built-in features for better email, calendar, and contact management.