Apr 07, 2026 07:00:00

I tried running the AI model '1-bit Bonsai 8B' with 8 billion parameters locally on my iPhone 17 Pro. Here's a review; it's easy to run using the free app Locally AI.

1-bit Bonsai 8B is an AI model released on March 31, 2026, by the AI development company PrismML. It is characterized by its low memory usage, with 8 billion parameters but only 1.15GB of memory. Another major feature of 1-bit Bonsai 8B is that it can be run locally on an iPhone 17 Pro, so I tried running it using ' Locally AI ,' which was introduced as a demo app on PrismML's official website.

PrismML — Announcing 1-bit Bonsai: The First Commercially Viable 1-bit LLMs
https://prismml.com/news/bonsai-8b

Locally AI - Local AI Chat App - App Store
https://apps.apple.com/jp/app/locally-ai-local-ai-chat/id6741426692

Once you open the Locally AI page on the App Store, tap 'Get'.

Once the installation is complete, tap 'Open'.

Once Locally AI starts, tap 'Continue'.

The model selection screen will appear, but since 1-bit Bonsai was not included in the initial model list, tap 'Skip'.

Tap 'Select a Model' in the center of the screen.

Once the list of models is displayed, tap 'Bonsai'.

Tap the download button located to the right of 'Bonsai (8B)'.

Please wait a while until the download is complete.

Once the download is complete, swipe down on the screen to close the model selection screen.

You're ready when 'Bonsai 8B' appears at the top of the screen. You'll also see 'Meet Gemma 4' in the center of the screen, but this is just text promoting Google's AI, Gemma 4, so you can ignore it.

Enter text at the bottom of the screen and tap the send button. This time, I wanted to check if it would respond in Japanese, so I typed 'Hello' and sent it.

My self-introduction was displayed immediately.

I typed 'Should I put a screen protector on my iPhone?' and sent it.

The AI models give varying answers to this question, but the 1-bit Bonsai 8B was in the camp of not applying it.

However, it's questionable whether they actually understood the question, as they inexplicably suggested PC disk protection as an alternative, and their response included phrases that were both understandable and difficult to grasp, such as, 'Keeping your iPhone screen clean is sufficient by either swiping your finger away from it or simply cleaning the screen.'

To test its ability to solve simple calculations, I entered the problem: 'You need 5 tomatoes to make 1 glass of tomato juice. How many tomatoes do you need to make 6 glasses of tomato juice?' It gave me the correct number of tomatoes along with a slightly questionable formula: '6 glasses x 5 tomatoes = 30 tomatoes.'

The benchmark results and download links for the 1-bit Bonsai 8B are summarized in the following article.

A memory-efficient AI model, '1-bit Bonsai,' has appeared, boasting 8B of parameters but consuming only 1.15GB of memory, while achieving performance equivalent to or better than models consuming 14 times more memory - GIGAZINE