Optimizely - A/B testing you'll actually use.
Acquainted - A simple tool to create conversational polls and surveys
Apptimize - Mobile A/B Testing for iOS and Android. Improve Your Native App Codelessly in Real-time.
Decision Jam - Make better decisions quickly with your team
AB Tasty - AB Tasty is an all-inclusive platform for conversion rate optimization, personalization, customer activation, and testing.
AbTest.io - A free url shortener with A/B testing features