Whatsmyserp - Powerful Rank & Serp Tracking. Completely Free.
SEOmator - SEO website analysis & audit tool
SendView - The best way to track your competitors' email marketing.
Check My Links - Highlights broken links on page
Seolyzer - Seolyzer is the ultimate SEO tool that provides you with all the information you need to improve your website’s health and performance.
SEOquake - SEOquake provides a browser extension to conduct on-page SEO audit.