LIKEtoKNOW.it - Shop your favorite Instagram accounts
Camelcamelcamel - Easily monitor Amazon product prices and get alerts when they drop.
Revlio - Make ads, posts & products shoppable using SMS & Instagram
Fetchee - Fetchee is a free price tracking wish list app that works with all online stores worldwide.
EtsyHunt - Backed by lots of top Etsy shop ideas, EtsyHunt builds tools that make Etsy SEO, products research, Etsy listing and tag optimization easy. Get it for free now!
Keepa - Price history charts and the option to be alerted on price drops for all Amazon sites.