You expose the service to get users to use your service and for client application developers - it is impossible for you today to build an application that inte

You expose the service to get users to use your service and for client application developers - it is impossible for you today to build an application that integrates all the services that your users want to use for very specific actions. It is also about getting data into your application; for users today the process of attaching an image/file that is in the cloud to an email is as follows. Edit email, open up file store (say flickr) download file, go back to email,find downloaded file, upload file and attach. With a cloud file picker solution this becomes a whole lot more integrated and as service provider it is in your interest to offer the ability for users to pick your files.