Read original post at Adam Grocholski's Blog
Users often want to save the highest level that they reached in a game and then continue playing at that level when they return to their game. Or they want to continue reading where they left off when they return to a book reader. One way you can enable this is by saving key-value pairs that persist on the user’s device between sessions and even after an app closes. In Android apps, these key-value pairs are called shared preferences. In Windows Store apps, they’re called application settings or just app settings.