D3.js - D3.js is a JavaScript library for manipulating documents based on data. D3 helps you bring data to life using HTML, SVG, and CSS.
Smaller - Make your websites load faster
Skuuudle - Discover, match and monitor your eCommerce competitors.
Website Grader - Grade your website's strengths and weaknesses in seconds.
Checkbot - Checkbot will boost the SEO, speed and security of your site by checking you're following 50+ web best practices. Browser extension with free and paid plans.
Textalyzer - Analyze text readability and SEO parameters