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

Marketo - Marketo's powerful marketing automation software helps marketers master the art & science of digital marketing to engage customers and prospects.

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

Constant Contact - Constant Contact offers email marketing, social media marketing, online survey, event marketing, digital storefronts, and local deals tools.

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

Omnisend - Omnisend - Marketing Automation for Ecommerce provides the omnichannel approach for sales-driven marketers that have outgrown the generic email marketing platforms.