Optimizely - A/B testing you'll actually use.
OctoPerf - OctoPerf is a SaaS load testing solution, based on JMeter.
VWO - Use VWO to tweak, optimize & personalize your website with minimal IT help.
StresStimulus - Load testing tool for websites and mobile that works with hard-to-test applications.
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.
SmartMeter.io - Performance Testing with Enterprise-Level Features with a familiar jMeter interface