Shortwave is a polished AI-native client, but it is Gmail-only and replaces your inbox. Here are five alternatives, including options that add Outlook and go deeper on follow-ups.
Shortwave is the most AI-native email client around, but it only works with Gmail (no Outlook, no IMAP) and it replaces your client. If you need Outlook support or want the work organised after triage, the Alkmist Inbox Agent is the strongest alternative: it reads Outlook and Gmail as one inbox, drafts in your voice, and chases stalled follow-ups. For raw speed, Superhuman. For an affordable cross-platform client, Spark.
Shortwave has real strengths. The common reasons people go looking for an alternative:
Shortwave does not support Outlook or IMAP, so anyone on Microsoft 365 is shut out from the start.
The thread-bundle interface is polished but takes adjusting to, and you move off your existing inbox to use it.
Shortwave excels at AI search, summaries and drafting, but it does not chase stalled follow-ups or turn email into tasks and projects.
Shortwave has restructured its plans several times in the past year, which makes budgeting harder.
Four questions that decide whether a tool actually sticks.
Layering onto Outlook and Gmail beats replacing your client or locking you to one ecosystem.
Labelling tidies the inbox. Ranking tells you the few things that actually need you today.
Drafting is table stakes. Chasing the threads that go quiet is what stops things slipping.
Watch for annual lock-in, per-seat costs, credit meters and overage fees in the fine print.
Ranked by how much work they take off your plate, with honest notes on where each falls short.
Reads every email in Outlook and Gmail, ranks the few that need you, drafts in your voice, and chases stalled follow-ups on its own. Groups email, docs and tasks into projects, with a built-in assistant (voice coming soon) and one Inbox Health score. EU-hosted, never trains on your mail, never sends without your click.
Trade-off: no in-meeting notetaker, and access is via waitlist while it rolls out.
A keyboard-first client with sub-100ms actions, AI drafts in your voice, instant replies and thread summaries. Works in Gmail and Outlook. Now owned by Grammarly.
Trade-off: it replaces your client, it is the priciest option here (from about $25 per user per month), and it is a single-player tool.
Readdle's email client for Gmail, Outlook, iCloud and IMAP, with AI Compose, a My Writing Style feature and a Smart Inbox. Strong free tier; Premium from about $5.99 per month.
Trade-off: it replaces your client, stores credentials on Readdle's servers, and reviewers find the AI lighter than dedicated tools.
A server-side overlay for Gmail and Outlook that sorts your inbox into categories, drafts replies in your voice, and takes meeting notes from your calendar. From about $22.50 per user per month on annual billing.
Trade-off: annual billing with possible volume overage fees, and a fixed category logic you cannot tune.
Sits in front of any IMAP inbox (Gmail, Outlook, Apple Mail) and learns which mail matters, moving the rest into smart folders. It also tracks emails you sent but did not get a reply to. From about $7 per month per inbox.
Trade-off: it filters, it does not draft, rank a single priority list, or chase follow-ups for you.
| Tool | Best for | Works in |
|---|---|---|
| Alkmist Inbox Agent (Pidgy) | Closing the loop across Outlook + Gmail | Outlook + Gmail |
| Superhuman | Raw speed | Gmail + Outlook (client) |
| Spark Mail | Affordable cross-platform client | Gmail, Outlook, IMAP |
| Fyxer | Drafts plus meeting notes | Gmail + Outlook (overlay) |
| SaneBox | Lightweight filtering | Gmail, Outlook, IMAP (layer) |
The Alkmist Inbox Agent reads Outlook and Gmail, hands you the five that need you, and chases the rest. Join the waitlist for early access.
