Office 365 Unified API Set

A new unified API set for Office 365 will make it easier to develop applications that access data, creating more opportunities to build and sell custom solutions that can access a user’s e-mail, calendars, contacts, files, and more. However, the unified API set is evolving and lacks some functionality, so developers who use it should plan for potential changes to their application code to make it compatible with the APIs when they become generally available, probably within the next few months.

New API Set Simplifies Cross-Service Access

In May 2015, Microsoft announced plans for a single set of Representational State Transfer (REST)-style APIs for accessing data from Office 365. REST-style APIs are commonly used for Web services and simplify access from client-side browser scripts and mobile applications, including those on non-Microsoft platforms such as Android and iOS.

Exchange and SharePoint already provide product-specific APIs that allow development of both server-side applications like Salesforce and SharePoint Online connectors and client-side applications such as mobile address book programs. For example, Exchange provides Exchange Web Services and SharePoint provides the SharePoint Client-Side Object Model. The Office 365 unified API set will replace the product-specific APIs, simplifying and extending programmatic access to data that users have stored in the cloud.