// on-device · open-source · offline
A dry stone wall stands without mortar. Drystone answers without servers — open-source models running entirely on your iPhone.
Why offline
Download a model once, then chat on a flight, on the fells, on the Tube. Replies stream from your phone's own chip — Apple-GPU accelerated, no signal required.
Chats encrypted at rest. Face ID lock. Incognito mode. A one-tap network kill switch with a transparency log. Erase everything whenever you like.
Drystone reads your iPhone's exact chip and memory, then recommends models that genuinely run well on it — from 1B featherweights to 7B on Pro devices.
Documents
Attach a contract, paper, or funding call straight into a chat. Drystone indexes it on your phone and answers from it — with the honesty to say when the answer isn't in the document. Confidential files stay confidential, because they never leave your hand.
Models
A curated catalog matched to your hardware, full Hugging Face search, and your own GGUF imports. Switch models mid-thought.
Setup
Free, no account. It opens straight into a chat — no forms between you and it.
The intro matches one to your exact iPhone. One download over Wi-Fi, a few minutes.
From then on it loads itself and answers offline. Airplane Mode is a demo, not a limitation.
Privacy, with receipts
Not a promise — an architecture. Every claim below comes with somewhere to check it.
Questions
Honestly: no. Phone-sized open models (1B–7B) are noticeably less capable than frontier cloud models. They are genuinely good at summarising, drafting, translation, and answering from documents you attach — and they work where the cloud can't follow: offline, and in confidence.
From 0.8 GB (Llama 3.2 1B) to about 4.7 GB (7B-class). You download once over Wi-Fi; after that, no connection is needed. Drystone tells you which models fit your phone before you download.
iOS 17 or later. Small models run on most recent iPhones; 7B-class models want a Pro model with 8 GB of memory or more. The app reads your exact device and recommends accordingly.
One thing, only when you ask for it: model downloads and searches to huggingface.co, over HTTPS. Every request appears in the in-app transparency log, and the offline lock blocks even those. AI answers never touch the network.
No. This page loads no analytics, no fonts from third parties, no scripts from anyone else — zero external requests. View source; it's all right there.
Atlantis Innovation Ltd, an innovation consultancy in Manchester, UK. Drystone began as a simple question — can serious AI run on a phone, privately? — and became the answer.