Chapter 1: Introduction & Concepts — what is Lyra Code?
This chapter is for complete beginners who are new to Lyra Code. If you've never heard of "APK", "API key" or "terminal" before, that's totally fine — we'll start from zero and explain every term, one by one.
Reading time: about 10 minutes.
1.1 Core concepts: spend 5 minutes to understand a few words
These words appear again and again throughout this documentation. Spend a few minutes getting familiar, and nothing will confuse you later.
1.1.1 What is an "AI model"?
An AI model (also called a large language model, or LLM) is like a "super brain" living on a remote server.
- It doesn't live on your phone — it runs on someone else's servers;
- Your phone sends it a question, and it sends back an answer;
- Common models include OpenAI's GPT series, Anthropic's Claude series, Google's Gemini series, and Chinese ones like DeepSeek or Moonshot (Kimi).
Key point: Lyra Code itself does not include a model. You need to choose a model provider and connect your phone to its servers before you can chat. How to connect is covered in Chapter 8 "Models & Providers".
1.1.2 What is an "API key"?
An API key is a "pass card" issued by your model provider, and it looks something like this:
sk-xxxxxxxxxxxxxxxxxxxxxxxx- It proves that "this phone is being used by me (a paying customer)";
- You sign up on the provider's website, top up some credit, and generate your own API key there;
- An API key is money and identity. Never post it online or share it in chat groups. If it leaks, other people can spend your credit.
1.1.3 What is an "Agent"?
An Agent means the AI doesn't just answer you — it takes action for you.
A normal chat app: you ask → it answers.
An Agent (Lyra Code): you say "unzip the downloaded archive and sort the images inside into my gallery folder" → it plans the steps by itself, reads the files, performs the operations — and asks for your permission before every step.
1.1.4 What are "commands / terminal / shell"?
- Command: a line of text instructions, like
ls(list files) orgit push(upload code); - Terminal: the window where you type commands;
- Shell: the program that translates and executes commands;
- Termux: a terminal app for Android — basically a command-line window on your phone.
In Lyra Code, the AI can use Termux to run commands for you (install software, run scripts, manage files). Configuration is covered in Chapter 2 "Installation & Setup".
1.1.5 What is a "workspace"?
The workspace is a dedicated folder. Lyra Code's AI is only allowed to read and write files inside this folder by default, so it can't mess with the rest of your phone.
- Default workspace:
/storage/emulated/0/Lyra(aLyrafolder at the root of your phone storage); - Put your project folders, writing drafts and so on here.
1.1.6 Termux, Shizuku and Root — what's the difference?
| Name | What it is | Privilege level | When you need it |
|---|---|---|---|
| Termux | A terminal app on your phone | Normal app | Running commands, scripts, installing software (almost everyone needs this) |
| Shizuku | A service that borrows system debug privileges | Higher (ADB level) | Advanced stuff like querying system info, batch-managing apps |
| Root | Full "jailbroken" super-user access to your phone | Highest | Very rare cases like modifying system files |
For beginners
You only need to set up Termux first. Ignore Shizuku and Root until you actually need them — you can come back and learn when the time comes (see Chapter 13 "Running Commands").
1.2 So what exactly IS Lyra Code?
In one sentence:
Lyra Code is an Android app that combines a local AI assistant, a file manager, a code editor and a universal toolbox.
Three things make it special:
1.2.1 Local-first (your data stays in your hands)
- Your model keys, conversations, files and account passwords are all stored on your phone;
- Unlike some apps, it does not upload your chats to its own servers for "relay";
- Your privacy stays between you and your model provider.
1.2.2 Agentic (AI can do things, but only after you approve)
- AI can read your files, edit your code, run commands and connect to remote servers;
- But every risky action pops up a confirmation dialog waiting for your approval;
- If you don't approve, it can't change anything. That's "controlled".
1.2.3 Extensible (build it like LEGO)
- Skills: install "skill packs" so the AI learns specific abilities (Chapter 18);
- MCP: a standard way to connect external tools and data sources (Chapter 15);
- Scheduled tasks: let the AI do something for you automatically every day (Chapter 17).
1.3 Is Lyra Code right for me?
✅ Good for you if…
- You want to write code, edit files and run scripts on your phone;
- You handle email, cloud drives or FTP servers a lot, and want AI to do the legwork;
- You're a writer or creator who wants AI help with writing, organizing and progress tracking;
- You want to experience "AI working autonomously but fully under your control".
❌ Not great if…
- You just want a chatbot for casual chat (a normal AI chat app is simpler);
- Your phone runs Android 8.0 or older (it won't run);
- You don't want to learn anything new and even approving permission pop-ups annoys you.
1.4 What can it do? (capability overview)
| Capability | Plain explanation | Example | Details |
|---|---|---|---|
| Model access | Connect multiple AI providers | Chat with Kimi, write code with Claude, switch anytime | Chapter 8 |
| Interface & chat | Four main screens, conversation operations and management | Create branches, archive conversations, chat with images | Chapters 3–7 |
| Agent tools | AI reads/writes files, runs commands, searches the web | "Find all the TODOs in this project" | Chapter 11 |
| Files & code | File manager + code editor | Unzip archives, edit code, preview web pages | Chapters 12–13 |
| Remote integration | SSH / email / cloud drive / FTP / MCP | "Download the logs from my server" | Chapters 14–15 |
| Mini server | Run a web server on your phone | Preview the website you're building | Chapter 16 |
| Scheduled tasks | AI works on a schedule | Generate a writing progress summary every day at 22:00 | Chapter 17 |
| Skills / memory | Install skills, let AI remember your habits | Install a "novel writing" skill pack | Chapters 18–19 |
| Backup | One-tap backup/restore | Export a full backup before switching phones | Chapter 20 |
| Stats & diagnostics | See token spending, check phone health | Compare which model costs less | Chapter 21 |
1.5 FAQ
Q: Is Lyra Code free? A: The app itself is free and open source. You pay the model provider (usage-based billing, usually very cheap).
Q: Do I really need an API key? A: Yes. Models run on provider servers and need a key to be called. Free tiers are tiny or nonexistent — top up a small amount (a few dollars lasts a long time).
Q: Can I skip Termux? A: You can, but the AI loses command execution and many advanced features won't work. It's recommended — configuration is in Chapter 2, 2.6.
Q: How do I move to a new phone? A: Use Backup: export on the old phone → import on the new one (see Chapter 20 "Backup & Migration").
Q: My phone is laggy — is it Lyra Code's fault? A: AI runs in the cloud; your phone doesn't run big models locally, so it shouldn't lag. Slowness is usually network or background tasks.
1.6 What to learn next
- Chapter 2: Installation & Setup — install the app on your phone and enable the Termux command channel (must read)
- Quick Start — configure your first model provider and send your first greeting
- Chapter 3: Interface Overview — get to know the app's four main areas
End of chapter · Next: Installation & Setup — install the app and enable the command channel