Optimizely - A/B testing you'll actually use.
Google Analytics - Improve your website to increase conversions, improve the user experience, and make more money using Google Analytics. Measure, understand and quantify engagement on your site with customized and in-depth reports.
SplitMetrics - SplitMetrics is the A/B testing platform for App Store and Google Play page to discover the most converting icons, screenshots, video, etc.
Mixpanel - Mixpanel is the most advanced analytics platform in the world for mobile & web.
Intellimize - Convert more. Optimize and personalize for every website visitor.
Matomo - Matomo is an open-source web analytics platform