nate - World's only universal shopping app
RetailMenot - The RetailMeNot mobile app allows you to find deals on the go for both online shopping and in store shopping.
Shipt - On-demand grocery delivery
Slickdeals.net - Slickdeals: The Best Deals, Coupons & Discounts on everything
Google Shopping - Find the best products, prices and places to buy
Honey - Honey is a browser extension that automatically finds and applies coupon codes at checkout with a single click.