Responsive design previews, accessed via the top bar of the frontend CNVS UI, allow you to preview your current state according to the responsive breakpoints you can set in the Breakpoints menu, under Additional Settings of the Configure Tab.
Mobile Preview – previews the scene according to how it would appear on mobile
Tablet Preview – previews the scene according to how it would appear on tablet
Then, in Initial States, found in the configure tab of the backend Canvas editor, you can select the states you fine tuned with the mobile and tablet previews, so that those will be the ones loaded on the selected device. It’s always advisable to check the scene on a real device as well.