Emmet Re:view is described as 'Emmet Re:View displays your responsive web-page in a number of views side-by-side so you can quickly test how web-page looks at different resolutions and devices' and is an app in the Development category. There are 2 alternatives to Emmet Re:view for Linux, Mac and Windows. The best alternative is Blisk, which is free.
Blisk is a browser for web developers, QA engineers, and web designers with built-in mobiles, tablets, laptops, and desktops. It provides teams and freelancers with a workspace to develop and test modern web applications twice faster.
Polypane is a browser built from the ground up to create websites and apps. Polypane is the only browser that lets you develop a website for all viewports and devices at once, and gives you the best overview of them. View your site at all sizes