Competera - Competera is a price tracking tool for performance-oriented eCommerce retail and brands of all sizes worldwide.
Camelcamelcamel - Easily monitor Amazon product prices and get alerts when they drop.
Keepa - Price history charts and the option to be alerted on price drops for all Amazon sites.
Inventory Spy - Spy how many products remain on any Amazon Product’s offer listing page.
aifora - Maximize profits with optimized and automated pricing and inventory management across all sales channels.
Asinhunt - Asinhunt was created to be a cheaper Jungle Scout (web app) alternative.