Project Hollow

Notes, tasks, files and conversations, connected in one workspace. Plan your day, shape an idea or ask Hollow to help with the next step.

Request accessExplore the apps

No AI training on your content
Two-factor sign-in
Export or delete your data

16 connected apps. One account.

studio.projecthollow.com/chat

Good afternoon, Alex

The apps

Pick the apps you need.

Start with the one you need today. They share one account, one shell and one search box.

Work

Plan the day and keep the essentials in order.

Create

Write, calculate, present and draw.

Communicate

Email and team messaging in the same workspace.

Build and run

The AI assistant, automation, monitoring and code.

In daily use

One day, four apps.

Write something down, turn it into a task, keep its files beside it and talk it through with your team. Each is its own app, in the same workspace.

Write it down and link it up.

Link one note to another as you type, then open the backlinks panel to see every note that refers to the one you are reading. Arrange ideas freely when a linear page is too restrictive, and see other people's live cursors when you share a notebook.

See Notes

Turn it into work.

The same tasks appear as lists, a Kanban board or a calendar, so moving a card between stages needs no second list. Drag a task onto the schedule to give it a day and a start time, and keep a Pomodoro focus timer in the side panel while you work through it.

See Tasks

Keep the files beside it.

Inline previews cover PDFs, code, images, video and Markdown, so a quick check does not mean downloading the file. Resumable uploads carry on after an interruption instead of starting again from the beginning.

See Files

Talk it through.

Use Spaces and channels for team discussion, and direct messages between friends for one-to-one chats. Threaded replies keep a discussion together, with per-user read tracking so you can see what is new.

See Yap

Hollow AI

Choose the model, then work across your apps.

One assistant that you can reach from any Hollow app, running on the model you pick for the task.

Google GeminiGemini 4 ArgonGemini 3.8 FlashGemini 3.5 Flash LiteNano Banana 2.1Nano Banana 2Nano Banana ProGoogle GemmaGemma 4 26BMeta LlamaLlama 4 ScoutLlama 4 MaverickAnthropic ClaudeClaude Sonnet 5Claude Sonnet 5.5Claude Haiku 5.5Claude Opus 5.5Claude Fable 5.1OpenAI GPTGPT-6 AstraGPT-6.1 SolGPT-6 LunaxAI GrokGrok 4.1 FastGrok 4.1 FastDeepSeekDeepSeek V4 FlashGoogle VeoVeo 3.1Veo 3.1 Fast

Choose your model

Pick the model that suits the task. The list follows Hollow’s own model registry, so it changes as providers release new models.

Works inside your apps

Open the assistant in any app, already aware of what you are looking at. Changes to your data are proposed first and wait for your approval.

Not used to train models

Your content is not used to train AI models. Each request goes to the provider that runs the model you chose, to produce the answer.

Meet Hollow AI

Platform

One platform under every app.

Search once and look across your apps, and link an item in one app to work in another. Each app is built on the same foundation.

Every Hollow app, from Notes to Cascade, draws on the same shared foundation.

See the platform

Trust

Plain facts about your data.

Where it lives, how AI requests are handled and what you can do with it.

Where your data is stored

Your account and workspace content are stored with Google Cloud (Firebase). The main database is in a United States multi-region location, and parts of Hollow run in London and the United States.

AI requests and training

Hollow does not train models on your content. AI providers handle requests under their business terms, which do not allow training on those requests. The privacy policy explains processing and retention.

Access is denied by default

Access is denied unless a rule allows it. The database and storage rules start closed and open only for the data you own or that is shared with you.

Your control

You can request an export of your data from your account settings, and download it when it is ready.

You can delete your account and its data from your account settings.

How we handle your data

Pricing

Four plans, from free.

Start on Seed and move up when you need more. Switch between monthly and annual billing to compare.

Seed

Try Hollow for free

£0free

Request access

Sapling

Hollow for your everyday life

£6.99a month

Billed monthly.

£6.49a month

£77.88 billed yearly.

Choose Sapling

Tree

Canopy

Deep AI, automation and coding capacity

£89.99a month

Billed monthly.

£81.99a month

£983.88 billed yearly.

Choose Canopy

No VAT charged.

Compare plans in full

Developers

Build on Hollow.

Drive your workspace from a terminal, call it over an API, or connect an AI client with MCP.

Install the Hollow CLI

$ curl -fsSL https://api.projecthollow.com/cli/install.sh | sh

For macOS and Linux. Then: hollow login, hollow whoami

Start building

Make it your own.

Begin with the app you need today and add others when the time comes. Nothing you have made gets left behind.

Hollow is invite only for now. Every account starts free on Seed.

Request accessSee pricing