Private AI memory · for your Mac · free

Own your brain.Rent the models.

Never explain yourself to an AI twice.

A quiet Mac app that remembers your work — and briefs whatever AI you're using with the right context before it acts. Encrypted on your Mac. Yours, not the model's.

60 seconds · no account · no API keys · macOS 26+ · Apple Silicon

We can't read your brain · nothing leaves your Mac · revoke any AI's access anytime
get_context_packet()Acme Corp
Confidence high. B2B SaaS, mid-market HR buyers intake · 95%
Confidence high. Brand voice: warm, no jargon CMO · today
Confidence unconfirmed. Budget ~$50k (unconfirmed) slack · 0.7
Don't mention the competitor teardown — confidential
Unknown: their 2026 headcount plan
ledger #8f2a · other projects sealed off

An example packet — real ones are built from your work.

The problem

You pay for the smartest AI in history.
It has amnesia.

Every new chat starts from zero. Who you are. What the project is. What was decided, what's off-limits, how you like things written. You explain it — again — to a machine you already explained it to yesterday.

That's not a quirk. That's your most valuable context, locked inside someone else's app.

Watch it work

Ask for a briefing. Context lands.

No browser extension, no setup. Hippo writes a short, cited briefing from your sealed brain — paste it in before you ask, in any AI.

chatgpt.com
Draft the outreach email to Acme.
Happy to help! Could you tell me a bit about Acme and what the email should cover?
Done — a warm, jargon-free note for Acme's mid-market HR buyers, anchored on their ~$50k range. I left the competitor teardown out.
V paste your briefing

Animated illustration of the Brief bar in action.

The obvious question

“Doesn't ChatGPT already have memory?”

It does — and it's genuinely useful. Here's the difference.

Their memory
  • Lives inside one app.
  • One big pile — work, clients, and personal life mixed together.
  • You can't see what it knows.
Your Hippo
  • Works with every AI you use — ChatGPT, Claude, whatever's next.
  • Sealed projects: one project's AI never sees another's.
  • Every fact has a receipt: inspect, edit, or delete any memory — and see exactly what was shared.

Keep their memory on. Hippo is the one that belongs to you.

The unit of value

It's not memory. It's a briefing.

The Context Packet is a contract Hippo hands an agent before it acts: what it knows, what was withheld, what's uncertain, what it must not do — every claim cited, every serving logged.

01

Scoped & cited

The right five memories, never five hundred — each traceable to its source, with confidence and freshness.

02

Walled off

Each project is a sealed brain. One project's AI never sees another's data — and you can prove it. Revoke any agent's future access in one click.

03

Shareable

Drop a packet into a doc or Slack thread. It's useful even to people who don't use Hippo yet — and it spreads.

The core primitive

One Hippo. Many projects. No leaks.

A project is an isolated, sealed brain. It can be a company, a client, a personal project, or your own work brain — whatever you keep apart in your head, you keep apart in Hippo. Projects never share data with each other. Per-project walls mean one project's AI never sees another's, and the Consent Ledger proves it.

How it works

Capture → compile → brief → govern

Quietly, from the tools where you already work. No second brain to garden — Hippo decides what's worth keeping and only asks you about the exceptions.

Capture

It notices what matters

From your chats, docs, and notes — read on your Mac, never sent to us. Off by default, conservative on purpose: Hippo remembers less than it could.

Compile

It gets sharper as you work

The Memory Compiler dedupes, resolves contradictions, and lets stale facts fade — so your brain stays current, not cluttered.

Brief

One click. Any AI.

Click “Get my briefing” and Hippo writes a short, cited briefing from your sealed brain. Copy & open ChatGPT, Claude — anything — and paste it in before you ask. (Global hotkey on the way.)

Why a hippo?

Meet your hippocampus.

It's the little seahorse-shaped part of your brain that turns today into memory. (Anatomists actually named it after the seahorse — hippokampos. We rounded up to something with more personality.)

Hippo does the same job for your work: quietly filing what matters so every AI you touch already knows the score. Calm, surprisingly fast, a little stubborn about your privacy — and it never forgets a project.

Get your Hippo
Pure zero-knowledge

Your brain never touches a server.

No copy of your memories, keys, or index ever leaves your Mac. Nothing of your brain to breach — it was never on our side.

  • Keys & plaintext stay on your Mac. The cloud only ever holds encrypted blobs. The index never leaves.
  • Every fact has a receipt. Every memory is inspectable, editable, deletable — and every answer drills back to its source.
  • Honest revocation. We cut off future access and log it. We never pretend a model "forgets" what it already saw.
  • Fiduciary by design. Never ads. Never data resale. Your brain is yours.
Consent Ledger
09:14Claude · read · Acme only
09:31ChatGPT · read · Acme only
11:02Accountant bot · read · finance only
14:20Grok · revoked · future access
14:21Write · "launch is Q3" · approved by you
Pricing

Free to start. Yours forever.

Self-serve, no sales calls. Your brain stays on your Mac on every plan.

Free
$0
to start
  • 1 project
  • Context Packets
  • Exceptions inbox
  • On-device, one Mac
Download free for Mac
Most popular
Pro
$19/mo
or $15/mo billed yearly — 2 months free
  • Unlimited projects
  • Sharper “boost” consolidation Arriving soon
  • Multi-device sync Arriving soon
  • Recovery kit Arriving soon
Get your Hippo

Cancel anytime. Your brain stays on your Mac either way — we can't hold your data hostage. We never had it.

Runs on Apple Silicon Macs with Apple Intelligence (macOS 26+) · free to start · no account