Jungle Scout - Amazon product research made easy.
Ubersuggest - Want more traffic? Ubersuggest shows you how to win the game of SEO. Just type in a domain or a keyword to get started.
Reviewbox - E-commerce data tool to monitor customer reviews, track online pricing, optimize AMS tools, and more from Amazon, Walmart, and other major online retailers.
Keyword Explorer by Moz - Find the best keywords to improve your website's SEO traffic
DataHawk.co - DataHawk software platform provides Amazon analytics tools for sellers and vendors to increase sales, optimize margins, gain insights, and boost productivity.
Content Marketing Stack - A curated directory of content marketing resources