Responsive Website Test - Test any website on desktop, mobile, and tablet
RetailMenot - The RetailMeNot mobile app allows you to find deals on the go for both online shopping and in store shopping.
Responsive Viewer - View multiple screen dimensions in one view
Honey - Honey is a browser extension that automatically finds and applies coupon codes at checkout with a single click.
LT Browser by Lambdatest - LT Browser is a free dev friendly browser for developers and testers. You can see mobile view of website on different screen sizes and resolution on 50+ pre installed view ports. You can build, test and debug your website faster then ever.
Slickdeals.net - Slickdeals: The Best Deals, Coupons & Discounts on everything