According to the documentation (2016.1) we can use either a system defined web application (/api/deepsee) or create a custom web application for handling requests. What are some reasons to use one rather than the other?
InterSystems IRIS BI (DeepSee) is a Business Intelligence (BI) technology that enables the real-time analysis of transactional data, and is designed to be optimal for embedding within transactional applications.