If we are going to make apps that offer our users significant features, then almost certainly we are going to need a way to manage, store, and filter significant amounts of data.
It is possible to efficiently store very large amounts of data with JSON, but when we need to use that data selectively rather than simply restricting ourselves to the options of "save everything" and "load everything", we need to think about which other options are available.
A good computer science course would probably teach the algorithms necessary for handling the sorting and filtering our data, but the effort involved would be quite extensive, and what are the chances of us coming up with a solution that is as good as the people who provide us with the Android API?
So often, it makes sense to use the solutions provided in the Android API. As we have seen, JSON and SharedPreferences classes have their place but at some point, we need to move on to using real databases for real-world...