Amazon Comprehend is a continuously-trained natural language processing service that can be used to perform entity detection, sentiment analysis and key phrases detection from unstructured data in English and Spanish languages. This service is released in 2017.
Comprehend is a great tool for automatically customer reviews and checking if the reviews are positive or negative. It could used to scan news article and to check if certain person is mentioned. It can also be used to perform topic modelling - that is to group documents based on the topic for the document.