Don't get it? Just highlight it.
Huadong is a system-level AI reading layer for macOS. Highlight text in any app, press ⌥⌘E, and the explanation appears right where you are — no window switching, no copy-paste, no interruption.
Installation guide & try it
Doubao· Balanced
Volcano ArkDone
In short: as of the end of June 2025 the online business base is still growing, but growth is starting to level off.
Put plainly, more people keep using the service — the increase is just slower than it used to be. That usually means the business has reached a relatively mature stage.
Two ways to get an explanation.
Works the moment it is installed, or plug in your own model.
Web session · No API key
Highlight text, press the shortcut, and the Doubao, DeepSeek or ChatGPT session you are already signed into answers in a dedicated explanation window.
- No API key — it works as soon as it is installed
- A separate explanation window per provider, so your existing chats stay clean
- Follow-ups stay in one thread; after 10 minutes it starts a fresh session
API overlay card · Your own key
The explanation appears next to the passage you are reading, streaming word by word, and you can keep asking.
- No app switching — your reading is never interrupted
- Collapses to a capsule at the screen edge when you switch away; one click brings it back, nothing lost
- Stop, retry, copy and pin
Available on the Chrome Web Store
Start with a highlight. Right in Chrome.
Highlight text on a webpage and ask Doubao, DeepSeek or ChatGPT to explain it. No Mac app or API key needed for the browser extension.
- 01
Open the store
Choose Add to Chrome, review the permissions, then confirm Add extension.
- 02
Pin for easy access
In Chrome’s Extensions menu, find 划懂 · 网页会话桥 and pin it. Pinning is optional.
- 03
Highlight and explain
Return here, select the sample sentence and right-click to ask Huadong for an explanation.
Installed? Try a highlight
Select the sentence below, right-click and choose “用划懂解释”. The extension currently uses Chinese menu labels.
Compound interest means that interest earned also earns interest in later periods.
Your selected text is sent to the AI service only when you trigger an explanation. Privacy policy ↗
Having trouble installing?
Open Chrome’s normal browsing window rather than Incognito or Guest mode. If installation is blocked on a work or school device, contact your administrator. If the right-click menu is missing, check that Huadong is enabled in Chrome’s extension manager and refresh this page.
Want shortcuts across Mac apps or the API overlay? Set up the Mac app →
Models you trust.
Eight major services, plus any OpenAI-compatible endpoint you host yourself.
Provider presets are only defaults — base URL and model name are both editable in settings.
Set up the Mac app in three steps.
Install
Open the DMG and drag Huadong into Applications. This test build is not notarized. If you trust its source and macOS blocks the first launch, use Open Anyway in System Settings → Privacy & Security.
Grant access
Tick Huadong under System Settings → Privacy & Security → Accessibility. Reading highlighted text across apps needs it.
Highlight
Select text in any app and press ⌥⌘E. ⌃⌥E, ⌃⌘E and the macOS Services menu work too.
Kept in the Keychain
Your API key lives in the macOS Keychain, on this device only
Only the selection
Never your window title, URL or surrounding content
No account
Nothing to sign up for, nothing to log into
No telemetry
This version uploads no usage data at all
Go highlight something.
Installation guide & try itWeb session mode is free. API overlay mode uses your own API key, billed directly by the model provider.