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