[SalesForce] How to view Salesforce1 on the desktop? (reloaded)

I've noticed that Lightning Experience (LE) uses the exact same URL as the S1 Mobile App: /one/one.app

  • Does it mean it is defacto the same app?
  • How can I view the S1 mobile app in my browser as I've done in Summer'15?

I tried to turn off LE again, but navigating then to /one/one.app only brings me:

You can't access Lightning Experience

The page you're trying to access
is available from the Salesforce1 mobile app only. Please try again
from a supported mobile device. Need help? Ask your Salesforce admin.

enter image description here

For development, support and usability I really don't want to use a mobile device, but I need to be able to access the app. Also I don't want to use an emulator.

Best Answer

The only way that Salesforce can tell whether you're accessing the page through a desktop or mobile browser is via the user-agent header. All you need to do is to change that header to identify yourself as a mobile browser.

There are plenty of tools that will help you with this. I use a plugin for Firefox called User Agent Overrider, but I'm sure there are many others.

In IE developer tools you can emulate a Windows Phone, which also allows you to see the SF1 web app.

If you connect programmatically, all you need to do is to add a mobile browser user-agent to your HTTP headers. Enjoy!