ChatNX

An AI chat client for the Nintendo Switch (homebrew). A native .nro app written in C++ with SDL2 and libcurl that talks to Puter's AI gateway over HTTPS, directly from the console.

Unofficial homebrew project, not affiliated with Nintendo.

Features

• Chat with multiple AI models (Claude, GPT, and more)
• Generate images from a prompt, with a built-in gallery and full-screen zoom/pan viewer
• Analyze a Switch screenshot by attaching it to your question
• Voice dictation with a USB microphone
• Live usage and quota tracking, with a per-model cost breakdown
• Full interface and AI responses in 28 languages

Screenshots

Requirements

• Nintendo Switch on Custom Firmware (Atmosphère)
• A Wi-Fi connection
• A Puter account and an API token (https://puter.com/dashboard#account)

Installation

Copy ChatNX.nro into the /switch/ folder on the SD card, or send it over the network with nxlink:

nxlink ChatNX.nro -a <switch-ip>

On first launch the app creates sdmc:/config/ChatNX/config.json. You can enter the token from inside the app (Y on the config screen) or edit that file directly:

{
  "puter_token": "<your token>",
  "model": "claude-haiku-4-5",
  "image_driver": "cloudflare-image-generation",
  "language": "en"
}

On a first launch the app picks the console's own system language (falling back to English); language only pins it to one of the 28 supported codes.

The token is never displayed or written to logs, and config.json is git-ignored.

Controls

Button	Action
A	Write a message / confirm
B	Back
X	New conversation
Y	Enter the token (config screen) / manage a conversation (sidebar)
+	Options
−	Show/hide the sidebar
L	Analyze a screenshot (pick one from the album)
R (hold)	Voice dictation
ZL / ZR	Zoom out / in (image viewer)
↑ / ↓	Scroll / navigate

In handheld mode the touchscreen works: tap the buttons, scroll the chat with a finger.

Building

Requires devkitPro with switch-dev and the portlibs switch-sdl2, switch-sdl2_ttf, switch-curl. From the devkitPro shell:

make            # or: ./scripts/build.sh

The .nro is produced at the project root.

Code layout

Headers live in include/, implementations in source/:

• main — initialization, main loop, input (pad + touch)
• ui — screen rendering and touch hit-tests (geometry in theme.h)
• gfx — drawing primitives (text, anti-aliased rounded rectangles)
• net — Puter client (chat and quota, on detached threads)
• store — persistence of conversations and config on the SD card
• i18n — translations (full UI and AI responses in 28 languages)
• util, json, album, keyboard — helpers (strings, parsing, screenshots, keyboard)

Notes

• The Puter quota is shared across all models.
• Conversations are saved on the SD card (custom .cnx format).
• The on-screen keyboard behaves better in handheld mode than docked.
• Responses are shown as plain text (any Markdown is stripped).

Acknowledgements

• Puter — the AI gateway behind chat and image generation
• devkitPro / libnx — the Switch toolchain and SDK
• SDL2, SDL2_ttf, libcurl, HarfBuzz and FreeType — rendering, networking, text shaping
• Noto Sans fonts and stb_image

License

Code under the MIT license (see LICENSE). Bundled third-party assets keep their own licenses: the Noto Sans fonts under the SIL Open Font License 1.1 (see romfs/NOTO-OFL-LICENSE.txt) and stb_image (public domain / MIT).