Appsero - Appsero is a killer WordPress Analytics, Licensing & Deployment Tool. Appsero is the perfect companion for WordPress plugin & theme developers.
Website Grader - Grade your website's strengths and weaknesses in seconds.
Squirrly SEO Focus Pages - Waze for navigating Google Ranking factors
Smaller - Make your websites load faster
Freemius - Freemius is a suite of solutions for monetization, analytics, and marketing automation for freemium and premium WordPress plugins.
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.