Cloud and CMS system are also services for users and developers to store and access data in servers. They offers direct access scalable storage and networking infrastructure as well as powerful authentication and data sharing mechanisms. And this is normally achieved by using Rest APIs.
REST-style architectures consist of clients and servers. Clients initiate requests to servers; servers process requests and return appropriate responses. Requests and responses are built around the transfer of representations of resources. A resource can be essentially any coherent and meaningful concept that may be addressed, ex. content in CMS system or a file in cloud.
By using Rest like API, your CMS system can be setup so that it serves as a centralized data reservoir where any mobile device or desktop can access by request through http protocol.
OAuth is an open standard for authorization. It allows users to share their private resources (e.g. photos, videos, contact lists) stored on one site with another site without having to hand out their credentials, typically supplying username and password tokens instead. Each token grants access to a specific site (e.g., a video editing site) for specific resources (e.g., just videos from a specific album) and for a defined duration (e.g., the next 2 hours). This allows a user to grant a third party site access to their information stored with another service provider, without sharing their access permissions or the full extent of their data.
List of OAuth service providers includes Facebook, Flickr, Foursquare, GitHub, Google, LinkedIN, etc. Through this open standardized authorization system, your CMS system can be consumers of all these great content sources.
Third party integration
Other than the main stream data sharing, QPLOT has done couple of third party integration in the past, including Infusionsoft (CRM), and Mirth Open Source HL7.