Camelcamelcamel - Easily monitor Amazon product prices and get alerts when they drop.
UserGuiding - Create in-app experiences with the most straightforward product adoption platform — quick implementation, lasting user engagement.
Keepa - Price history charts and the option to be alerted on price drops for all Amazon sites.
Usetiful - Fight user churn with great user onboarding. Interactive product tours and smart tips significantly improve your user retention.
Fetchee - Fetchee is a free price tracking wish list app that works with all online stores worldwide.
Userlane - Digital adoption platform with interactive guidance for software applications allowing anyone to understand and master any software from the get-go.