Mailspring

Transform email management through a beautiful cross-platform client that indexes messages for instant Gmail-style searches across all connected accounts. Compose professional correspondence with rich signature editors supporting images and social links, unify multiple email accounts into streamlined inbox views, translate messages between English, Spanish, Russian, Chinese, French, and German automatically, check spelling with automatic language detection, accept calendar invitations directly from your inbox, customize appearance through multiple themes and layouts, and unlock advanced capabilities including message snoozing, read receipts, link tracking, and contact enrichment across Mac, Linux, and Windows systems.