Lean Analytics - A/B testing React apps made easy
Decidr - Make better decisions with quick A/B polls
SEOTesting.com - Easily track the changes you make to pages and websites, to see if they have an effect on Google rankings and clicks.
Zoho PageSense - The Complete A/B Testing and Website Optimization Software for Marketers.
GoodUI Evidence - People's A/B test results that show which UI ideas work best
Keyword Explorer by Moz - Find the best keywords to improve your website's SEO traffic