A local AI companion is an app that runs a language model on your device. LLM (large language model) is the neural network that generates replies. Because the model runs on the phone, your chats stay on the device and work in airplane mode.
Most companion apps use model families like Gemma, Llama, Phi, or Mistral. The exact names change over time, but the setup pattern is the same: install the app, download a model file, and start talking.
Before installing anything, check your device:
Пример:If your phone shows “Storage almost full” in Settings, that is a warning. A 2 GB model will not fit on a device with only 1.5 GB available.
These apps give you a chat window, a model download button, and simple settings. They are best for beginners.
Пример:After installing such an app, you open Settings, tap “Download model”, and choose a small version. The download bar usually starts immediately.
Termux is a terminal emulator that provides a Linux-like environment on Android without root. `llama.cpp` is a program that runs language models on ordinary CPUs.
This route is for enthusiasts who do not mind typing commands.
Пример:In Termux you would run:
pkg install llama-cpp
llama-cli -m /sdcard/Download/model.gguf -p "Hello, how are you?"The `-p` flag sets the starting prompt. The terminal prints the model’s reply after a few seconds.
Why this works: `llama.cpp` is compiled for low-resource devices, and Termux gives the needed environment.
If you want to test models on a PC first, read our guide on How to Run Android Apps and Games on PC: Emulators, Waydroid, and Cloud Services. The same model file can often be reused later on Android.
Hybrid apps work online normally and switch to a local model when the network is unavailable. This suits users who want fast answers on Wi-Fi and private chats on the go.
Setup is usually a toggle in the app settings: “Prefer offline mode” or “Local model”.
For a wider view of useful AI apps, check Best AI apps for Android in 2026.
Compare four things:
1. **Model support.** Look for apps that let you pick model size and format. GGUF is a common format for local models.
2. **Offline mode.** Check if the chat itself works in airplane mode after the initial download.
3. **Memory.** The companion should remember previous messages. Look for “context length” or “memory” in the description.
4. **User interface.** Try the free version first. A good interface matters for daily conversations.
Пример:If the developer writes “supports GGUF”, you can use models in that format. If the app only accepts one fixed model, ask yourself whether that model fits your phone.
| Approach | Best for | Typical device needs | Price |
|---|---|---|---|
| Ready-made companion app | Beginners, quick private chat | 6–8 GB RAM, 5–10 GB storage | Free or one-time payment |
| Termux + llama.cpp | Enthusiasts who want control | 8 GB RAM, 10+ GB storage | Free (open source) |
| Cloud + local fallback | Users who need both online and offline | 4–6 GB RAM, 2–3 GB storage | Subscription or freemium |
This simple test works for most ready-made companion apps.
1. Install the app from Google Play.
**Expected result:** you see a welcome screen asking for a model download.
2. Open the model download section in Settings.
**Expected result:** a list of model sizes appears.
3. Choose the smallest model, usually under 1 GB.
**Expected result:** the download starts. When finished, the chat window becomes active.
4. Write a short greeting in airplane mode.
**Expected result:** the model replies without a mobile connection.
Why do this: a small model reduces the risk of crashes. Once it works, you can try a larger model and compare quality.
1. **The app crashes after loading the model.**
Symptom: the screen freezes or the app closes on the first message.
Solution: download a smaller version of the model. Many pages offer 1 GB, 3 GB, and 5 GB variants.
2. **The download stops at 90%.**
Symptom: you see an “Error downloading model” message.
Solution: delete old videos or unused apps, then restart the download. The model needs the full amount of free space at once.
3. **The app says “unsupported model file”.**
Symptom: the file is downloaded, but the app refuses to open it.
Solution: look for a GGUF model and choose a common quantization like `Q4_K_M`. This combination works with most Android tools.
For a complete installation walkthrough, see How to Run an AI Model Locally on Android: Apps and Setup.
Will these apps work completely offline?
Yes, that is the main point. You only need internet to download the app and the model. After that, airplane mode is fine.
My phone has 4 GB of RAM. Can I use a local companion?
You can, but stick to small models. Expect slower replies and close other apps during chat.
How much storage do I need?
A small model can be under 1 GB, a medium model is 2–5 GB, and large models go beyond 10 GB. Check the model page before downloading.
Is my conversation private?
With a fully offline app, your messages stay on the device. If you enable cloud fallback, messages may go to the provider’s server.