When developing apps for Android, you never have to start completely from scratch, as the Android platform does a really good job of supplying a wide range of prebuilt UI components that you can simply drop into your UI.
This means that the same UI elements crop up time and again in all sorts of Android apps. So, it's well worth spending some time seeing what we can learn from other Android applications—particularly apps that do UI well.
In this section, we'll analyze the Google+ app, which comes preinstalled on many Android devices, and is also available to download for free from Google Play. We'll work our way through all the core UI components that Google uses in this app and look at what makes them so effective.