Use browser to debug mobile formatting

Currently, when I want to see how my app looks on a mobile device, I use the android emulator. This works fine as long as I’m just changing the design. Debugging is possible, but so much more comfortable in the browser.

So I wonder: Wouldn’t it be possible to restrict the browser viewport to make it look like a mobile screen?
Can I somehow set up that the browser shows the exact same app layout that would be shown on an android phone?

This would definitely speed up my development workflow.