Camelcamelcamel - Easily monitor Amazon product prices and get alerts when they drop.

Olapic - Olapic is a visual marketing platorm.

Fetchee - Fetchee is a free price tracking wish list app that works with all online stores worldwide.

Boo.st - Buy and sell everywhere using #hashtags.

Keepa - Price history charts and the option to be alerted on price drops for all Amazon sites.

Engagehub - Create social hub to assemble users’ activities through social media.