Big ideas.
Every screen.
Put any page in a phone frame. Pick a device, rotate it, or resize the viewport to find the details that need a little more care.
Explore phone viewBuild with an AI agent beside your page, inspect the details and check the result in the browser.
The tools you need to build for the web, right where you browse it.
Put any page in a phone frame. Pick a device, rotate it, or resize the viewport to find the details that need a little more care.
Explore phone viewChromium DevTools are one shortcut away. Inspect a layout, debug JavaScript, or see what happens when a connection slows down.
Meet your developer toolsDeveloper windows have their own session. Try a test account alongside your everyday browsing, with cookies and storage cleared when you close the last developer window.
Discover developer windowsA closer look at what is built in and how to use it.
Yalqen runs on Chromium, so pages render and debug the way they do in Chrome. On top of that it builds in the tools web developers usually add with extensions. Open the command bar with ⌘L and type > to see every developer command.
Open the AI panel with ⇧⌘A and choose Claude, Codex or Gemini. Select a project folder to explore and edit its code, or ask about a page without choosing a project. Agent setup and authentication depend on the provider you choose.
Attach open tabs or pick an element to give the agent context. In Verify mode, it checks changes in the browser; Review mode investigates without editing files, and Design mode focuses on the interface with screenshots before and after. Browser checks can run a user flow or scan responsive layouts.
Using AI sends your prompts and attached page content to the selected provider. Browsing itself does not require an AI session. Provider usage limits and charges are separate from Yalqen.
Press ⌥⌘M to show the page inside a device frame, and ⇧⌥⌘M to rotate it. Responsive mode lets you drag the frame to any size, or focus its handle and resize with the arrow keys.
| Device | Viewport (CSS pixels) |
|---|---|
| iPhone 15 | 393 × 852 |
| iPhone 15 Pro Max | 430 × 932 |
| iPhone 16 Pro | 402 × 874 |
| iPhone SE | 375 × 667 |
| Pixel 8 | 412 × 915 |
| Pixel 9 | 412 × 924 |
| Galaxy S24 | 360 × 780 |
| iPad mini | 744 × 1133 |
Test loading states and slow connections per tab: Offline, Slow 3G, Fast 3G or Fast 4G. Turn throttling off again with one command.
Match requests by URL pattern and decide what happens to them, without a proxy or a local server. Each rule can:
Rules are saved, can be edited from the command bar, and are switched on per tab.
prefers-color-scheme, then go back to the system theme.prefers-reduced-motion.One command resets every override on the page.
Choose Developer in the sidebar’s session switcher to open a developer window. It runs in its own session, apart from your everyday browsing, so you can sign in to a test account without logging out of your real one. Ad blocking and third-party cookie blocking are off there, closer to what most visitors’ browsers do. Cookies, storage and cache are wiped when the last developer window closes.
The full Chromium DevTools open with ⌥⌘I, and the page source with ⌥⌘U. Every other shortcut is on the keyboard shortcuts page.
Use the Mac developer browser guide to try a responsive form, a failing API and the same flow across Chromium, WebKit and Gecko before choosing your setup.