Chatbox

If you hold API keys for a few model providers, or run Ollama locally, what you need is a decent chat window — not a browser tab per vendor, an account per vendor, and conversation history scattered across all of them.

Chatbox is that window. 41,438 stars, GPL-3.0, with builds for Windows, macOS, Linux, iOS, Android and the web. Enter your API keys, or the address of a local Ollama instance, and switch models freely inside one interface — you can even change model mid-conversation and continue.

What it does well:

• Conversation history is stored locally rather than on a third-party service. (When using a cloud model, message content necessarily goes to that provider — but the history itself stays on your machine.)
• Prompt template management: save frequently used role definitions and instructions and apply them to a new conversation in one click instead of re-pasting.
• Local model support: connect Ollama and it works entirely offline, suitable for sensitive material.
• Image input, file parsing, Markdown rendering and code highlighting cover everyday needs.

The business model needs stating: this project has both a free open-source track and a paid service. The GPL-3.0 build on GitHub is complete and free, used with your own API keys. Separately, the company offers a paid Chatbox AI subscription that bundles model access so you do not have to obtain keys yourself. What we list here is the open-source, bring-your-own-key path, which carries no ads and no feature limits. The official site promotes both, so check which one you are downloading.

Note also that bringing your own key means model usage is billed directly by the provider. Chatbox takes no cut — but that portion is not free, so go in aware of it.