Based on our record, Responsive Viewer seems to be more popular. It has been mentiond 2 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Bonus! Useful Chrome extension for Responsiveness Testing. - Source: dev.to / 11 months ago
This chrome extension with all of the breakpoints set up https://chrome.google.com/webstore/detail/responsive-viewer/inmopeiepgfljkpkidclfgbgbmfcennb. Source: over 1 year ago
Invision - Prototyping and collaboration for design teams
Responsinator - Designed to test responsive websites on different devices.
Marvel - Turn sketches, mockups and designs into web, iPhone, iOS, Android and Apple Watch app prototypes.
Responsive Website Test - Test any website on desktop, mobile, and tablet
UXpin - Design is really about solving problems. UXPin is the UX Design Platform that gets that right.
Multi Screen Test - Test your site at different screen resolutions & devices.