Optimizely - A/B testing you'll actually use.
Maxymizely - Simple integration, all types of analytics, and A/B testing with one tool.
Evolv - Evolv is the visual editor for web-based projects that are used to find better ways to connect with customers in order to improve marketing economics.
VWO - Use VWO to tweak, optimize & personalize your website with minimal IT help.
SplitMetrics - SplitMetrics is the A/B testing platform for App Store and Google Play page to discover the most converting icons, screenshots, video, etc.
Intellimize - Convert more. Optimize and personalize for every website visitor.