Quartz

Quartz turns Gmail into a focused inbox. Every message is auto-sorted by how much it deserves your attention -- Critical, Routine, FYI, Icebox, Noise -- so important mail gets room to breathe and everything else collapses out of the way. The categories are yours to define, and Quartz learns them over time. Two things make it different. Privacy: all AI runs on your device (Apple Silicon), your mail is end-to-end encrypted with keys only you hold, and nothing is ever uploaded -- Quartz is CASA Tier 2 certified. Voice: when Quartz drafts a reply, it writes in your own cadence and warmth, informed by the thread and your relationship with the sender, not in generic LLM tone. Works on top of Gmail. Mac + iOS. Free during the private beta.