Introduction to the Cloud - Beginning iOS Cloud and Database Development - page 14

Designing for the cloud takes an understanding, from an iCloud standpoint, of how it synchronizes
data across devices. So, when you're working with your JSON, you have a good understanding
of what it takes to read data from a dedicated source, or know how to access that data in your
application and display the data once you receive it. This requires a clear understanding that your
local application is highly dependent on network connectivity. You also need to consider if there
needs to be an offline mode and how that impacts your application. If offline is a consideration, then
you need to set up a protocol for syncing when offline. You want to show this in the UI. I discuss
caching and taking data from the cloud and accessing it later. In programmer's terms, this is the API
(Application Programming Interface).
For the most part, users want to access to data, and if that data changes, they want to know
immediately through a push notification or an update to the application. All you need to do is make
sure that you have an understanding of how your application will handle the data and what data
will be driving the majority of the app after it has been downloaded. Think about this when you're
designing your core application: the data from the cloud is going to be a large part of it and having
access to the updated data or showing your users that there is other data available will be of utmost
importance. Once users can look at the application, they should see the data on the cloud versus
the local data. It is very important for your user to know they are looking at the right data, as this
service is meant to have a seamless interface and a user experience that doesn't do a lot of work
in front of the user. Users want to know that the work is going on behind-the-scenes and that they
have the most up-to-date content without having to check and be sure.
What Are iCloud's Key Offerings?
Apple announced its iCloud service in 2011 with the advent of iOS 5. In the most basic terms, iCloud
is simply an open directory on Apple servers that can connect with applications. While Apple has
used its experience in marketing to give their product an interesting name, in actuality it is simply a
box performing “server-side scripting” that would take an expert developer a lot of time to set up.
iCloud provides solutions for the problems of both digital storage and file sharing between devices.
It allows digital content to be continuously updated and synced on all of the user's devices without
making the user think about it. iCloud is designed to enhance Apple applications and improve
the user's experience by using Apple's servers to sync files and data. Once a user's app has the
necessary connections to work with iCloud, it does all the hard work for them. In virtually real time
it syncs all the data, so there is no more worrying about whether data has been copied to each of a
user's devices—it has. iCloud has many other functions, such as storing several types of data.
When iCloud is enabled on an app on a device, any update made to that application is automatically
sent out to iCloud, and any time any other changes come in from any other device, iCloud sees
the updated file and makes sure that the same applications on the user's other linked devices also
receive the updated file. Figure 2-1 shows this concept.