Optimizely - A/B testing you'll actually use.

SplitMetrics - SplitMetrics is the A/B testing platform for App Store and Google Play page to discover the most converting icons, screenshots, video, etc.

Adobe Target - Adobe Target provides an intuitive user interface and an expanded personalization toolset.

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.

invesp Pii Testing Engine - invesp Pii testing engine offers A/B testing solution for site optimization.

Chartbeat - Chartbeat shows you real-time traffic to your website and allows you to set alerts for any downtime or spikes in traffic.