Cloister AI
Confidential AI, offline.
A general-purpose AI assistant that runs entirely on your iPhone. Built for the work you cannot paste into a cloud chatbot — contracts, case notes, patient records, payroll, board papers. No account, no server, nothing to leak.
- Platform
- iOS
- Requires
- iOS 26
- Devices
- iPhone and iPad. Open-weights models need an iPhone 15 or newer.
- Pricing
- Free tier with usage limits. Pro subscription unlocks the rest, billed by Apple. Pricing is set on the App Store.
Built and priced in App Store Connect. Awaiting submission.
What it does
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01
Vaults
Ask questions across your own documents — PDFs, scans, photos, notes, saved pages. One vault per client or matter, and every answer cites the document it came from. Scanned paper is read on-device.
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02
Private meeting notes
Live transcription with a summary, the decisions taken, and action items attributed to the person who owns them. Audio is never written to disk: speech becomes text as it happens and the samples are discarded.
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03
Redact
Permanently flattens names, emails and phone numbers out of PDFs and photos — not a black rectangle you can drag off, the pixels are gone. Pro adds financial and identification numbers.
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04
Your choice of model
Ships with a small bundled model that works out of the box. Download larger open-weights models when you want more, or use Apple's own on-device model. Nothing is downloaded without you asking.
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05
Hands-free and everywhere
Voice conversation, on-device text recognition for photos and screenshots, memory that carries across chats, and Apple Health insights that never leave the phone.
Privacy, in full
Every model runs on your device. Nothing is transmitted unless you turn on an optional feature, and each one is named below.
Everything that leaves your device
| What | Who receives it | Where | Why | Trigger |
|---|---|---|---|---|
| The name of a model you chose to download | Hugging Face | United States | Fetching open-weights model files you explicitly requested | You choose |
| A search query you typed, when web search is enabled | DuckDuckGo | United States | Answering with current information and citations | You choose |
| A request for the voice pack and pronunciation dictionary | Hugging Face and GitHub | United States | One-time download of text-to-speech assets | You choose |
| A web address you paste or open | The website you chose | Wherever that site is hosted | Reading a page you asked the app to read | You choose |
- Web search is switched off by default. Turning it on is the only way a question you type reaches a third party, and the app tells you so at the moment you enable it.
- The app declares background audio so a meeting keeps transcribing when your screen locks. It does not record in the background at any other time.
- Subscriptions are handled by StoreKit on the device. There is no analytics SDK and no subscription service — nothing about your purchase reaches us.
Where your content lives
Everything — chats, vaults, documents, meeting notes, memory — is stored only on your device. There is no account and no server-side copy. Subscriptions are verified on the device by the App Store, so no purchase record is sent to us. Deleting the app deletes the data.
Analytics
None. No usage statistics, crash reports or telemetry are collected.
Permissions it asks for
- Microphone
- Meeting transcription and voice conversation. Audio is processed live and never saved.
- Speech recognition
- Turning speech into text on the device.
- Camera
- Photographing a document to add it to a vault.
- Health (read only)
- Optional health insights. Read on the device, never transmitted, never written back.
- Reminders
- Pushing action items from a meeting into your reminders.
- Calendar (write only)
- Creating follow-up events. The app cannot read your calendar.
AI disclosure
Cloister AI generates text with a language model. Output can be wrong and should be checked before you rely on it. Nothing you type is used to train any model — training would require sending your data somewhere, and the app does not send it anywhere.
Models
- Apple Foundation Models (on-device)
- Qwen3 0.6B, bundled
- Qwen3 4B, Gemma 3 4B and Llama 3.2 3B, downloadable
Licensing
Bundled open-weights models are Apache 2.0. Licence text is included in the app under Settings, Model licences.