SendView - The best way to track your competitors' email marketing.
SEOmator - SEO website analysis & audit tool
Owletter - Keep an Eye on Your Competitors' Newsletters
Whatsmyserp - Powerful Rank & Serp Tracking. Completely Free.
Competitors App - Competitors App helps marketers monitor their competitors' marketing moves in one place, with very little time investment.
Seolyzer - Seolyzer is the ultimate SEO tool that provides you with all the information you need to improve your website’s health and performance.