The best email clients in 2026

Across the top-reviewed set, the category splits between developer delivery tools, classic personal inboxes, and productivity-first team clients. Resend and similar platforms suit apps that need dependable transactional sending, logs, and webhooks, while Gmail remains the default for broad everyday use thanks to search, filtering, and tight ecosystem ties. For heavier workflows, Superhuman emphasizes speed, keyboard control, AI drafting, and follow-up management.