Klaviyo - Klaviyo helps brands own the customer experience, grow higher-value relationships, and deliver more personalized marketing experiences across email, mobile, and web.

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

Criteo - Build, scale, and activate first-party audiences with The Commerce Media Platform.

Clean Email - Clean Email is an online service that empowers you to take control of your mailbox.

Campaign Monitor - Email marketing software built for designers and their clients to run successful email campaigns.

Nylas Mail - The Nylas Cloud API powers your application with email, calendar & contacts features. Built-in features for better email, calendar, and contact management.