AWS Personalize - Real-time personalization and recommendation engine in AWS
Recombee - Recommender system as a service that uses advanced Machine Learning and Artificial Intelligence algorithms. Easy to try and evaluate.
RecoMind.io - Personalized recommendations at scale
Wylei - Wylei, a pioneer in Predictive AI cloud-based machine learning and marketing automation, creates & delivers real-time, personalized content.
Microsoft Azure Recommendations - Predict what your customers want and increase catalog discoverability
Optimizely - A/B testing you'll actually use.