Email automation is a critical feature that allows marketers to send targeted emails based on specific triggers. Tools like Mailchimp and GetResponse excel in this area, offering pre-built workflows and customizable triggers. SendinBlue also offers robust automation, allowing for complex scenarios involving both email and SMS. Constant Contact provides automation features but is more suited for smaller businesses with simpler needs. HubSpot, on the other hand, offers highly sophisticated automation capabilities integrated with its CRM.