Nano Chat GitHub

Chat with AI that lives on your phone.

Nano Chat talks to AI models that run on the phone itself, so nothing you write leaves it. Each companion is one ongoing chat, like a contact, with its own name, colour and personality.

Download the APK Source on GitHub

Android 12 or newer. Gemini Nano needs Google AICore, on recent Pixel and Galaxy phones. Gemma 4 E4B needs a phone with 12 GB of memory.

Companions, kept like contacts

A fresh install has three companions. New friend makes another. Each has a name, a colour, a personality written in plain words, and a model. The personality goes to the model with every reply.

The home screen, with each companion and their last message Editing Nano: name, colour and personality

Two models, both on the phone

Gemini Nano is the default. It is built into recent Pixel and Galaxy phones, needs no download in the app and costs it no memory.

Gemma 4 E4B is a larger model you download once, 3.7 GB from Hugging Face. It replies better, follows a personality more closely, and understands photos and voice notes. It needs a phone with 12 GB of memory or more.

Each companion picks its own model. Photos and voice notes stay in the app’s private storage.

Basil, on Gemma 4 E4B, answering a photo of a fridge with two dinner ideas Basil answering a voice note with a recipe

A companion can use your phone

With Handset installed, turn on Use this phone in a companion’s edit sheet. Handset shows what Nano Chat asks for, with every source off until you switch it on.

The companion can then search what you saw on screen and in notifications, catch up on messages, read a day’s timeline, open apps, set alarms and timers, switch Do not disturb, and control what’s playing. Each step shows as a line under the reply. Tap it to see what came back.

A companion takes at most 3 steps per reply, and can’t tap or type. The README lists the rest of its limits.

Nano searching the phone for a word, then opening Clock, with a line under each reply for the step it took The sheet for one step: what Nano searched for and what came back

Install it

  1. On the phone, download nano-chat.apk and open it. Android asks once to allow installs from your browser or files app.
  2. The releases page lists each APK’s SHA-256 and signing certificate, so you can check what you install. A newer APK installs over the old one and keeps your chats.
  3. Open Nano Chat and say hello to Nano. To try Gemma 4 E4B, pick it for a companion and start the download.

Privacy

Chats run on the phone. The app has no account, no analytics and no server of its own. It uses the network for two things: downloading Gemma 4 E4B from Hugging Face, and talking to Handset on the phone itself.

Turning on Use this phone gives a companion whatever you allow in Handset, such as notifications or location. The model reads that text to answer you. It stays on the phone, but it is in the chat from then on.