RetailMenot - The RetailMeNot mobile app allows you to find deals on the go for both online shopping and in store shopping.
LoveSales - Find and save products you love, get alerted when they go on sale.
Dealspotr - Dealspotr is like Wikipedia for deals.
TrackIf - Alerts you if the price of your favorite products drop
Honey - Honey is a browser extension that automatically finds and applies coupon codes at checkout with a single click.
Giftwhale - Giftwhale allows you to create personalised wish lists online.