Keepa - Price history charts and the option to be alerted on price drops for all Amazon sites.
Shipt - On-demand grocery delivery
Camelcamelcamel - Easily monitor Amazon product prices and get alerts when they drop.
Google Shopping - Find the best products, prices and places to buy
Shopping.com - Shopping.com is a leading price comparison site that allows you shop online for the best deals and lowest prices. You can read unbiased product reviews and compare prices online. Online shopping has never been as easy!
HOT DROPS - The fashion search engine personalised to your style