OneSignal is an entirely free application that allows user to send unlimited push notifications to unlimited subscribers. It supports all platforms such as HTML and also integrates well with WordPress. It provides real-time tracking feature to track notifications instantly after sending it. The software has A/B testing feature, which enables user to try different messages to smaller set of visitor to figure out effective message. It also has automatic notification feature that automatically sends notifications to the customers. This feature notifies the customer every time when new post is published. The software is capable of delivering a huge number of notifications in a very quick time.