Your AI Chief of Staff

Most AI waits for you.
Cossi doesn't.

It's 6:47am. Your alarm hasn't gone off. Cossi already knows James is drifting, your 10 AM needs the note you forgot to send, and Tom's flight moved — so tomorrow just rewrote itself. Wake up. Press play. Walk in ready. Nothing left your phone.

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People
Relationship pulse
Your network
SM
Sarah Mitchell
3 days ago · Strong
JK
James Kessel
18 days ago · Drifting
TP
Tom Parker
47 days ago · At risk
✦ Nudge
James is in your Q2 planning session today — good moment to reconnect.
📋
Brief
💬
Chat
📅
Calendar
✉️
Mail
⚙️
Settings
Good morning, K.
Monday · 3 meetings · Amber
KA
Day pressure
✦ AI Brief
Moderate day. Q2 planning is the priority — James hasn't seen the budget revision yet. Two drafts awaiting your review.
Q2 Planning — Kessel, Mitchell
09:30 · Zoom · 60 min
▶
Amex Strategic Review
14:00 · In person · 90 min
▶
1:1 with Sarah M.
16:30 · Zoom · 30 min
▶
📋
Brief
💬
Chat
📅
Calendar
✉️
Mail
⚙️
Settings
✦
Cossi
On-device · Private
Draft a note to James — let's reconnect before our session
✦
Hey James — it's been a few weeks. Looking forward to Q2 planning today. Want to grab 10 min beforehand to sync on the budget numbers?
✓ Draft saved for your review
Set a follow-up for next Thursday
✦
Done. Follow-up with James added to Calendar for Thursday 09:00 and linked to your tasks.
Message Cossi…
↑
📋
Brief
💬
Chat
📅
Calendar
✉️
Mail
⚙️
Settings
🔐Post-quantum encryption
📱Runs entirely on-device
🚫Zero telemetry
🔑24-word seed recovery
✅Human-in-the-loop always
The mental load

You shouldn't have to
remember everything.

Every day, you're carrying dozens of invisible commitments.

I need to reply to Sarah.
I promised I'd send that proposal.
I should check in with James.
What am I supposed to prepare for this meeting?
When can I actually get this done?
Did I follow up on last week's decision?

Cossi remembers so you don't have to. It finds what matters, tells you what's next, and quietly keeps the promises you already made.

Not another app to manage. A Chief of Staff that manages with you.

Built for

For people with
too much context.

Eight meetings before lunch. Fifty active threads. A calendar that runs your life instead of you. Cossi is the person in the room who remembers everything so you can concentrate on the one thing that only you can decide.

Chief of Staff
The principal's intelligence layer
Managing a principal's calendar, relationships, and information flow across 50+ stakeholders — while keeping nothing sensitive in a cloud tool.
Cossi gives you a morning brief of everything your principal needs to know. Relationship drift alerts before the meeting where it matters. Draft outreach that waits for human approval.
See how it works for CoS →
Founder / CEO
Context at scale
Context-switching between investors, customers, and team — while keeping 100+ relationships from going cold and decisions from compounding into bottlenecks.
Cossi surfaces who you've neglected in your network and drafts the reconnect message before you've opened email. Open decision tracking so nothing stays unresolved past three weeks.
See how it works for Founders →
Partner / GP
Relationship capital, protected
Managing portfolio relationships, LP communications, and deal flow context across a network of 200+ people — none of which should live in a CRM someone else controls.
Relationship health scores for every contact. Drift alerts before a relationship slips below threshold. Full context on your device — encrypted, post-quantum authenticated, recoverable only by you.
See how it works for Partners →
Senior PM / Consultant
Stakeholder intelligence
Maintaining context across multiple products or clients — with dependencies, decisions, and follow-ups that span weeks and span organisational boundaries.
Open decision tracking, per-meeting audio briefs, and follow-up reminders — all surfaced in a single spoken brief each morning. Client data stays on your device.
The loop

Cossi runs the loop
so you don't have to.

Every other tool is a place to write things down. Cossi is the loop that runs on top — five steps, every day, in the background, on your phone. You never open it and find it hasn't been working.

01 · Brief
Wake up briefed.
Before your alarm, Cossi has read your calendar, your contacts, and yesterday's threads. It plays you the day in 90 seconds while the kettle boils.
“You have 4 hours of focus before your 2 PM. James is drifting. Proposal follow-up is due today.”
02 · Prepare
Walk in ready.
Fifteen minutes before the meeting, your phone buzzes with the one thing to land — pulled from prior notes, open threads, and what only you would remember.
“Q2 planning in 15 min. James hasn't seen the budget revision. Bring it up early.”
03 · Act
Move things forward.
Cossi drafts the reply, proposes the time, captures the commitment — and waits. Nothing sends, nothing books, nothing changes until you press approve.
“Draft ready for Sarah. Proposed Thu 10:00 for the reconnect. Nothing sends until you say go.”
04 · Remember
Nothing falls through.
Every meeting, promise, and open decision becomes part of a memory that lives on your device forever — encrypted with a key only your seed phrase can unlock.
“Kept: your promise to send the deck by Friday. Linked to James, tagged Q2, surfaced Thursday.”
05 · Anticipate
Tomorrow, already handled.
While you sleep, Cossi notices what shifted — a flight, a cancellation, a slipping thread — and rewrites tomorrow around it. You wake up to a day that's already been repaired.
“Tom's flight moved. Rescheduled the 3 PM. Prep note updated. You have 20 more minutes for the deck.”

Brief. Prepare. Act. Remember. Anticipate.
It runs the loop. You run the day.

Why only Cossi

Cloud AI can't run this loop.
It needs your life on its servers.

To brief you, prepare you, remember you, and anticipate for you — an AI needs your calendar, inbox, relationships, and commitments live, all day, forever. Every cloud AI would need to hold all of it on servers you don't control.

Cossi runs on your phone. That's the only place a loop like this is safe.

It's not a privacy stance.
It's the reason the loop exists.

Under the hood

Six systems, one loop.

The loop is what you feel. These are the six systems working beneath it — connecting your calendar, contacts, email, and commitments into one live picture. Everything on your device. Nothing on a server.

🌅
Morning Brief
Daily AI briefing synthesising calendar, tasks, relationships, and open decisions. Day pressure score, nudges, and a 90-second spoken read-out.
🎧
Audio Meeting Prep
Tap play on any event. Cossi reads you a structured brief: attendee context, agenda, open interdependencies, and the one thing that matters.
👥
Relationship Pulse
Health scores for every person in your network. Drift alerts before relationships fade. Voice notes that surface automatically in your next meeting brief.
✍️
Draft Outreach
One tap to draft a context-aware message for any contact. Sits in a review queue — nothing sends until you approve it.
📬
SMTP/IMAP Email
Connects directly to your inbox via standard protocols. Drafts emails, summarises threads, and surfaces what needs a response. Credentials stay on your device.
🔒
Encrypted Vault
AES-256-GCM encrypted notes and context, signed with ML-DSA-65 (Dilithium). Recoverable via your 24-word BIP-39 seed phrase. No server required.
Loop step 01 · Brief

You wake up. Cossi already worked.

While you slept, Cossi read your calendar, cross-referenced your relationships, and rewrote your day around what actually matters. No setup wizard. No prompting. You just press play.

📊

Day pressure score

Green / amber / red signal based on meeting load, overdue tasks, and conflict detection — at a glance.

🔗

Interdependency alerts

Cossi detects when an open decision blocks a meeting, or when a relationship hasn't been touched before an important call.

▶️

Audio meeting briefs

Tap play on any event. A 4-section spoken brief covers context, stakeholders, open threads, and the 80/20 lever.

Good morning, K.
Monday · 3 meetings · Amber
KA
Day pressure
✦ AI Brief
Moderate day. Q2 planning is the priority — James hasn't seen the budget revision. Amex deck is not prepared for the 14:00 session.
Q2 Planning — Kessel, Mitchell
09:30 · Zoom · 60 min
▶
Amex Strategic Review
14:00 · In person · 90 min
▶
⚠ Conflict
Amex deck unfinished. Scheduled tonight conflicts with Tom's call.
📋
Brief
💬
Chat
📅
Calendar
✉️
Mail
⚙️
Settings
Loop step 04 · Remember

Nothing about a person
should be lost.

Cossi keeps a live picture of every relationship — recency, warmth, open threads, promises made. You see drift before a relationship goes cold, not after.

📈

Relationship health scores

Interaction frequency, recency, and signal diversity combined into a single 0–100% score per contact.

🎙

Voice notes per contact

Record a note about anyone. Cossi transcribes it and surfaces it automatically the next time that person appears in a meeting brief.

📅

Follow-up tracking

Set a reminder and Cossi creates both a task and a calendar event. Pending follow-ups surface in your morning brief.

People
Relationship pulse
Your network
SM
Sarah Mitchell
3 days ago · Strong
JK
James Kessel
18 days ago · Drifting
TP
Tom Parker
47 days ago · At risk
✦ Nudge
James is in your Q2 session today — great moment to reconnect. 18 days since last contact.
📋
Brief
💬
Chat
📅
Calendar
✉️
Mail
⚙️
Settings
The loop, in a day

From first alarm to end of day,
never behind.

This is what the loop feels like from the inside — a Monday where every meeting is already prepared, every relationship already tracked, and every promise already kept.

6:47am
Morning brief plays while you make coffee
Three meetings today. Two drafts awaiting your review. James Kessel — 18 days without contact — is in your 9:30 Q2 planning session. Cossi flags it before you've touched your phone.
9:15am
Tap play on Q2 Planning
90-second audio brief: James's context, the open budget thread he hasn't seen, and the one thing that needs to land in this meeting. You walk in prepared.
1:45pm
Conflict alert before the Amex review
Cossi flags that the strategy deck is unfinished and that a call you scheduled tonight conflicts with prep time. You reschedule before it becomes a problem.
5:30pm
Draft a reconnect note to Tom Parker
47 days of no contact. You ask Cossi to draft a note. It writes one, in your voice, using context from your last interaction. It waits in the review queue — nothing sends until you approve.
All day
Your calendar, contacts, and emails never left your device
Not by policy. By architecture. There is no server that could have received your data. The AI that powered all of this ran entirely on your iPhone.
The category doesn't exist yet

Cloud AI waits — because it has to.
Cossi doesn't — because it lives on your phone.

A tool built to run continuously — noticing, preparing, remembering, anticipating — can't do that from a cloud you'd never let touch your calendar, email, and relationships around the clock. The loop only works because it lives on the device that already holds your life.

Capability Cossi ChatGPT / Claude Notion AI
Runs entirely on-device ✓ ✗ ✗
Calendar & email stays local ✓ ✗ ✗
Automated morning brief (no prompting) ✓ ✗ ✗
Relationship health tracking ✓ ✗ ✗
Audio meeting prep briefs ✓ ✗ ✗
Post-quantum authentication ✓ ✗ ✗
Works without internet ✓ ✗ ✗
Human approval before any outbound action ✓ Manual only Manual only
General knowledge & writing Via opt-in API ✓ ✓

* ChatGPT/Claude can be connected via opt-in API key — your key goes phone-to-provider directly, never through Cossi's servers.

Trust

Private by architecture.

Your life is personal. Your Chief of Staff should be too. Cossi has no server-side accounts, no analytics pipeline, no AI API calls. The intelligence runs on your device. Your contacts, calendar, emails, and vault never leave your hardware.

This isn't a policy we could change. There is no server that could have received your data — because there is no server.

0
Data points sent to any server
AES-256
Vault encryption standard (GCM)
ML-DSA-65
Post-quantum auth (CRYSTALS-Dilithium)
24
Word BIP-39 seed phrase — your only recovery key
Getting started

Three steps.
Then the loop starts.

No account. No password. No cloud sign-up. You leave with the loop already running.

🔑

Create your seed phrase

Generate a 24-word BIP-39 phrase. This is your master key and your recovery mechanism — store it offline. No email. No password. No account.

🧠

Download an on-device model

Choose from the in-app model library. Models run fully offline via llama.rn — no API key, no usage fees, no data sent anywhere.

✦

Your brief is ready

Connect your calendar and email. Cossi begins building your intelligence layer immediately. Your first morning brief is waiting when you wake up.

Get your Chief of Staff.
Your day, already handled.

Download tonight. Wake up tomorrow to a life you don't have to catch up on. No subscription. No cloud. No data harvesting.

It runs the loop. You run the day.

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Scan to download Cossi

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