For Apple Mail on the Mac
Reply to emails faster — without switching mail apps
The work is rarely in the reading. It is in the composing: opening politely, making the point, forgetting nothing, closing warmly. MailTwin takes over exactly that part — in your own writing style, inside Apple Mail.
How it works
Select a message in Apple Mail and type the points the answer should cover — “Friday doesn’t work, propose Tuesday, ask about the invoice”. MailTwin writes the full reply from that. You read it, change what you want, and send.
The style comes from your own sent mail, which MailTwin reads once, locally, and separately for each account. Your work mailbox does not end up sounding like your personal one. Switch mailboxes and the register switches with you.
What it actually saves
Check it against your own numbers rather than ours: the email time calculator asks two questions and shows what answering costs you per week and per working year. It is deliberately conservative, needs no signup, and nothing you type leaves your browser.
The honest limit: MailTwin removes the composing, not the deciding. If a reply takes two minutes and thirty seconds of that is working out what to say, you get the ninety seconds of typing back — not the thirty seconds of judgement.
Your mail stays where it is
MailTwin runs no AI service of its own. You choose the provider from eight options and supply your own key; the request goes straight from your Mac to them. With Apple Intelligence or Ollama it never leaves the machine at all — no key needed, no network involved.
The sent mail your style is learned from never leaves the Mac. Indexing starts only when you start it — not at launch, not on a timer, not in the background.
Common questions
Do I have to switch mail apps? No. MailTwin runs in the menu bar and as an extension inside Apple Mail's compose window. Your accounts, rules and mailboxes are untouched.
What does it cost? $19.90 once for one user, $49.90 for five. No subscription. 30-day full trial, no card required.
Which languages? The interface ships in fifteen languages. Replies are written in the language of the incoming message — an English mail gets an English reply, a German one a German reply.
Requirements? macOS 13 or later and Apple Mail. For Apple Intelligence as the engine: macOS 26 on a supported Mac.
MailTwin is a menubar app for Apple Mail on macOS 13 or later. Eight AI providers with your own key; Apple Intelligence and Ollama need none and keep everything on the Mac. No MailTwin server in the AI path. $19.90 once, 30-day trial, fifteen languages. Built by Smilodon AS, Norway. mailtwin.ai · calculator