A local-first personal agent · Mac & iOS

Your day, announced
before it arrives.

Posthorn reads your email, calendar, messages, and chat — quietly, in the background — and surfaces the few things that actually need your attention. Local-first: your data never leaves your devices.

Free during beta · Mac today, iOS coming · Private by design

Today7:30 AM
Reply needed

Paul is waiting on your notes from the Lumen call before he flies out.

Calendar

Theo’s appointment moved to Thursday 2:00 PM — it overlaps your 1:1.

Handled

Filed 2 receipts, archived 9 newsletters, snoozed 3 low-priority threads.

Reads everything, in one place

EmailCalendariMessageSlackGoogle ChatTelegram

Less inbox. More day.

Posthorn does the reading, the triage, and the busywork — so the only things left for you are the ones that are actually yours.

01 · Reads

Reads quietly in the background

Connect Gmail, your calendar, iMessage, Slack — whatever you live in. Posthorn watches it all and sorts the signal from the noise, so nothing important hides in a thread you never opened.

Inbox
For youFYIEverything
AC

Aria

Can you grab Theo from practice at 5?

For you
St

Stripe

Your payout of $4,200 is on the way

Handled
#

#eng

Deploy is green — v2.3 is live

FYI
PS

Paul

Did we lock the Q3 numbers?

For you

02 · Surfaces

Surfaces what needs you

A short brief — every morning and through the day — naming the few things that actually need you, and why. One tap to act on any of them; the rest stays out of your way.

Today7:30 AM

Good morning. Three things need you.

Paul needs the Lumen call notes before he flies out. Aria asked about Theo’s pickup. And your 2 PM moved — it now clashes with Dr. Harrison.

Draft the notesReschedule 2 PMReply to Aria

03 · Acts

Handles the busywork

It drafts replies in your voice, reschedules, and chases the threads worth chasing. You stay in control — nothing goes out until you say so.

Draft reply

Paul · Conduit

“Did we lock the Q3 numbers? Need them before my flight.”

Posthorn drafted

Hi Paul — yes, Q3 is locked: $1.2M ARR, up 18% QoQ. Full breakdown’s in the shared deck. Safe travels.

Approve & sendEditNot now

Private by design

Your life stays on your devices.

A personal agent only works if it can see your most private corners — so Posthorn is built to keep them private. It runs on your Mac, reasons about your messages locally, and never parks your inbox in someone else’s cloud.

On-device first

Your messages are read and reasoned about on your Mac — not in someone else’s cloud.

Encrypted sync

When iOS lands, your devices stay in step over end-to-end encrypted sync.

You own your data

No inbox sitting on our servers. You decide what, if anything, ever leaves your device.

Built for people with too many inboxes.

Founders running more than one company. Operators holding a dozen threads. Parents keeping a household on the rails. When your attention is the bottleneck, Posthorn is the quiet hand that keeps the important things from slipping.

Questions, answered.

What can Posthorn read?

Email (Gmail), your calendar, iMessage, and chat — Slack, Google Chat, and Telegram. You connect only the accounts you want, and you can disconnect any of them at any time.

Where does my data live?

On your device. Posthorn is local-first — your messages are processed on your Mac, and your inbox is never uploaded to our servers.

Which platforms are supported?

Mac today. iOS is on the way, with end-to-end encrypted sync so your phone and laptop share the same brain.

What does it cost?

It’s free during the private beta. Join the list and we’ll reach out as spots open up.

Wake up to a quieter inbox.

Join the private beta and let Posthorn announce your day before it arrives.

Mac today, iOS coming

Posthorn — Your day, announced before it arrives