AMZScout - AMZScout extension will help you make a decision about picking a niche based on the actual data, not intuition.

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

dotdigital Engagement Cloud - View all of dotdigital's omnichannel marketing automation features: Email, SMS, Push Notifications, Social Ads, Live Chat, Segmentation, Marketing Automation and more

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

Topia - Create amazing wallpapers for your iPhone

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