RetailMenot - The RetailMeNot mobile app allows you to find deals on the go for both online shopping and in store shopping.
Paribus - Find out for free if online stores owe you a refund!
Dealspotr - Dealspotr is like Wikipedia for deals.
Lolli - Earn bitcoin when you shop online
Honey - Honey is a browser extension that automatically finds and applies coupon codes at checkout with a single click.
Slice Watch - Get an email when an item you've added drops in price 💸