I'm a full-stack web developer, and I built a free Chrome extension called Mobile View to solve something that kept slowing me down at work.
When you build responsive sites, you constantly need to check how a page looks on mobile while you're working on the desktop version and the usual options either hide one layout when you switch, or feel clunky. The part that really pushed me to build this was demoing work: when a client or an employer asks "how does it look on a phone?", screen-sharing a narrow browser window never looks great.
