Camelcamelcamel - Easily monitor Amazon product prices and get alerts when they drop.
Zalando - Zalando is a online retailer, offering Fashion and Lifestyle products.
Fetchee - Fetchee is a free price tracking wish list app that works with all online stores worldwide.
Fasttech - Fasttech is one of the best platforms for buying gadgets and electronics at the best rates.
Keepa - Price history charts and the option to be alerted on price drops for all Amazon sites.
Aliexpress - AliExpress is the largest e-commerce site in the world!