One of the most exciting new features in iOS5 is the iCloud. It is a very cool way of easily making it possible for iOS applications to sync data to the cloud. Apple provides an easy to use API which makes the remote saving of data as easy as saving a file locally.At a first glance in would seem that this would be the dropbox killer. A really frequent use case for many people is for dropbox to be used with their iDevices. Using dropbox to store their data remotely.
Apple as usual isn’t chasing what their competitors do. Instead they are walking their own walk, and doing what makes sense in their environment. They aren’t trying to provide the general file storage and sharing capabilities that dropbox provide, instead focussing on making it easy for a single “application” and “user” to share it’s files between devices. The advanced folder sharing capabilities of dropbox, and the independence of files and applications provided, aren’t given by iCloud. Apple let’s you store your stuff on the cloud, but keeps things “sandboxed” to your application.
There’s three key terms above: application, user, and sandbox.
- An application is defined by the application key provided by apple. Each application has it’s own unique key.
- A user is specified using an Apple ID. appleid.apple.com . This is the id that you use for interacting with apple to do things like buy stuff from iTunes etc.
- A sandbox is a way of providing limited access to a particular resource. The apple sandbox is a tight one, coupled to the application id. Applications on iOS devices have the ability to interact with files on the local filesystem, but only within their local sandbox. They are not able to share files between applications.
The sandbox has been continued with iCloud. Applications can only access files within their own sandbox. While it is possible to share files between a laptop, an iPhone and a iPad easily, it is not possible to share files between two different applications. Also iCloud does not support sharing files between users. These two key limitations are why iCloud is not going to replace dropbox.
