The experience of your web content on mobile operates very differently than what users experience on the desktop. The Chrome DevTools allow you to inspect, debug, and analyze the on-device experience with the full suite of tools you're used to, meaning you can use the tools in your desktop Chrome to debug a page on mobile Chrome.

Debugging occurs over USB and as long as your mobile device is connected, you can view and change HTML, scripts and styles until you get a bug-free page that behaves perfectly on all devices.

Remote Debugging - Chrome Developer Tools — Google Developers.