For consultants and coaches

For consultants and coaches: the follow-up, the recap and the polite no

The work is the conversation. The email is what happens around it: the follow-up after a discovery call that has to land while they are still interested, the proposal, the session recap that turns an hour of talking into three actions, the scheduling, the invoice that was due on the first, and the request to pick your brain over coffee that deserves a kind decline rather than silence. None of it is the work. All of it decides whether there is more work.

MailTwin writes those emails from your notes. You type the points, it writes the finished message in your own words, and you read it and send it.

What that looks like after a call

Select the message in Apple Mail, type what the reply needs to say, and MailTwin writes the complete email into the reply window — greeting, every point in full sentences; Mail appends your own signature.

You type	You get
good call, proposal by Friday, three-month engagement, two days a month, kick off in May	A follow-up that thanks them without gushing, sets out the shape of the engagement and names the date the proposal arrives
recap: three actions agreed, hiring decision by month end, delegate the weekly reporting, next session the 22nd	The session recap with the actions listed properly and the date of the next one, in the voice they hear in the room
no free calls now, 45-minute paid intro instead, booking link, happy to answer one quick question by email	A boundary that is warm and unmistakable, with the door left open exactly as far as you want it
invoice 4,200 was due the 1st, gentle nudge, same bank details, tell me if it's stuck with finance	The chase that gets paid without souring the relationship

The point is not that any of those is hard. It is that there are fifteen of them a week and they arrive between calls.

Your voice is what they hired

A consultant's email is a sample of the consultant. Clients notice when the follow-up reads like a template, and the ones who pay well notice fastest. MailTwin reads your own sent mail, on your own Mac, and copies your habits: how you open, how direct you are, whether you write in short declaratives or long considered sentences. It never writes a sign-off of its own; Mail appends your signature. The draft is a first pass by something that has learned your habits. The judgement in it stays yours, because you read it before it goes.

Two practices, two registers

Many people in this work run more than one thing: the consulting practice and the coaching practice, the business address and the personal one, the firm you left and the one you started. MailTwin learns voice separately for every mail account, from that account's own sent mail. Each keeps its own register, switching mailbox switches the voice, and nothing is shared between them.

Fees, dates and the terms of an engagement

A proposal with the wrong day rate in it is a conversation you cannot fully recover from. When MailTwin rewrites a draft you have already written, a validator checks the result before it reaches you and rejects it if a number, a date, an amount, a link or an email address has changed. That runs every time. What it cannot do is judge whether a new sentence is true; type the wrong kick-off month and you will get it back in a well-written sentence. Reading the draft is still your job, and nothing sends without you.

The thread from a client you have not spoken to since March

A long engagement leaves a long thread, and the client who comes back after six months expects you to remember all of it. MailTwin summarizes the thread and pulls out what was agreed and what is still open, which is worth more than the email it then writes. It also improves a draft you have already written, including inside Mail's own compose window, and translates when a client writes in another language.

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 your practice, and anyone quoting a precise figure is guessing. What holds is where the time goes: not into the one proposal that matters this month, but into the fifteen follow-ups and recaps around it, written at the end of a day of calls.

What it will not do

It does not connect to a CRM, a scheduling tool, an invoicing app or your notes, and it does not know what you agreed on a call unless you type it. It will not read your inbox on its own, answer anyone without you, or send anything you have not looked at; there is no autonomous mode and no scheduled sending. It is macOS 13 or later only, Apple Mail only, with no iPhone or iPad app, so the follow-up you want to send from the train waits until you are back at the Mac. It needs two macOS permissions on the first run, Automation for Mail and Accessibility, which is a few minutes of clicking in System Settings and cannot be automated away, because Apple deliberately does not let an app grant itself access to your mail. And if your replies are mostly one line, it will not help much.

Where client correspondence goes

MailTwin has no AI of its own. You choose one of nine engines and supply the key. Three of them, Apple Intelligence on macOS 26 or later, Ollama, and a local OpenAI-compatible server (oMLX, LM Studio, llama.cpp), run on the Mac itself, and with those the message is never transmitted at all. With a cloud provider, the request goes from your Mac straight to that provider, along with a short sample of your own sent mail so the reply sounds like you. Your voice index stays on the Mac. Nothing goes to MailTwin, because there is no MailTwin server and no MailTwin account for it to go to. Whatever confidentiality you have promised a client under an engagement letter remains yours to honour in that choice; if the answer is that their material does not go to a cloud service, the on-device engines are a complete answer.

Common questions

My voice is the product. Will this flatten it?

It is built the other way round. It reads your own sent mail, on your own Mac, and copies your habits: how you open, how direct you are, how long you let a sentence run. It never writes a sign-off of its own; Mail appends your signature. Every draft is one you read and can change before it goes, so the judgement in it stays yours.

Can it keep two practices apart?

If they are separate accounts in Apple Mail, yes. Voice is learned separately for every mail account from that account's own sent mail, so the consulting address and the coaching address, or the business one and the personal one, each keep their own register. Switching mailbox switches the voice, and nothing is shared between them.

Could it change a fee or a date?

When it rewrites a draft you have already written, a validator rejects the result if a number, date, amount, link or email address has changed. What it cannot do is judge whether a new sentence is true, so a wrong kick-off date you typed comes back written out neatly. Read every draft before it goes. Nothing sends on its own.

Does client correspondence go to a third party?

You choose the AI engine from nine. Apple Intelligence on macOS 26 or later, Ollama, and a local OpenAI-compatible server run on the Mac itself and transmit nothing. With a cloud provider the request goes from your Mac straight to that provider under your own key, with a short sample of your own sent mail for the voice. There is no MailTwin server and no MailTwin account in the path. Whatever confidentiality you have promised a client remains yours to honour in that choice.

Is it a subscription?

No. It is a one-time licence, with a 30-day full trial and no card required to start. If you pick a cloud engine you pay that provider for what you use, typically a few cents a day at ordinary email volumes, and the app shows a running total.

Try it on a month of follow-ups

Thirty days, every feature, no card. A month with a proposal in it is the only honest test.

Download MailTwin →

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