Mimestream, the Gmail client for macOS founded by former Apple Mail engineer Neil Jhaveri, this week ended more than two years of beta development with the official release of Mimestream 1.0. As a native app written in Swift and designed with AppKit and SwiftUI for a clean, stock appearance, Mimestream's UI will be familiar to many Apple Mail users, but the app is exclusively for accessing Gmail (support for other services is being considered). Mimestream uses the Gmail API rather than a standard IMAP connection to support features like categorized inboxes, aliases and signatures, server-side filters, templates, labels, vacation responses, mentions, undo send, archive, and more. Support for multiple Gmail accounts is included with a unified inbox, and the app…