MailTwin
Email help for people who run the business and answer the email
If you own a small business, you are the sales desk, the support desk and the accounts department, and all three arrive in one inbox. The hours do not go into the hard emails. They go into the twenty easy ones, the ones where you already know the answer and still have to write it out politely.
MailTwin does that part. You type a few notes, and it writes the whole email for you, in your own words.
What that looks like on a Tuesday
Select the customer's message in Apple Mail, type the points your answer needs to make, and MailTwin turns them into a complete, properly written email — greeting, every point in full sentences, sign-off — which you read and send.
| You type | You get |
|---|---|
| back in stock Friday, happy to hold one, postage is £3.95 | A full reply confirming the restock date, offering to reserve one, and stating postage, in your usual register |
| viewing Thursday 2pm, bring ID, parking behind the building | The complete appointment email with all three details spelled out |
| date's free, full day is the package they want, deposit holds it | An enquiry answer that confirms availability, names the package and explains the deposit |
| can't do Tuesday, Thursday works, quote goes over tonight | A polite reschedule with the commitment attached |
Three things that matter more than the demo
It learns how you write. Not a generic business voice, yours. It reads your own sent mail on your own Mac and copies your habits. And it does that separately for every mail account, so your work address and your personal address keep their own register.
It works in the app you already use. Apple Mail, on a Mac running macOS 13 or later. Nothing to migrate, no forwarding, no second inbox, no change of address to tell your customers about.
You buy it once. Not another monthly bill. Thirty-day trial, every feature, no card to start.
The honest version of the time saving
Christopher Naas, who makes MailTwin, says it saves him an hour or more on a busy email day. That is his experience, not a promise about yours, and anyone quoting you a precise figure for your inbox is guessing. What is reliably true is the shape of it: the routine replies stop being the thing you do instead of going home.
What it will not do
It will not read your inbox on its own, answer anyone without you, or send anything you have not looked at. It will not help much if your email is mostly one-line replies. It is Mac-only, Apple Mail-only, and there is no phone app. And it needs two macOS permissions on the first run, Automation for Mail and Accessibility, which takes a few minutes of clicking and cannot be skipped, because macOS deliberately does not allow an app to grant itself access to your mail.
About the AI part, in plain words
MailTwin does not have its own AI. You point it at one of eight engines and it uses that. Two of them, Apple Intelligence and Ollama, run on your Mac, so the email never leaves the machine. The rest need a key from that provider, which typically costs a few cents a day at ordinary email volumes, and the app shows you a running total so there are no surprises. There is no MailTwin account and no MailTwin server in the path.
Common questions
How does MailTwin save a small business owner time?
It writes the routine replies. You type the points the answer needs to make and it produces the finished email, so the twenty easy messages stop taking an evening. It does not answer anything on its own and it never sends without you reading it.
Do I have to change my email address or my email app?
No. MailTwin works inside Apple Mail on your Mac, with the accounts you already have there. Nothing moves, nothing forwards, no new inbox to learn.
Will it sound like a robot wrote it?
It learns from your own sent mail, on your own Mac, so it copies your habits: how you open, how long your sentences run, how you sign off. Each mail account learns separately, so the business address does not start sounding like the one you use with family.
Is it a monthly subscription?
No. It is a one-time licence, with a 30-day full trial and no card required to start.
Does my customer email get sent to some company's server?
You choose the AI engine. Two of the eight, Apple Intelligence and Ollama, run on your Mac and send the message nowhere. With the others the request goes from your Mac straight to that provider. There is no MailTwin server in the path.
Try it on your own inbox
Thirty days, every feature, no card. The only test that settles it is a week of your own mail.
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