[Tech Notes] Android basics II - Android SDK building blocks

A few objects are defined in the Android SDK that every developer needs to be familiar with. There are the building blocks of your android applications.

The most important ones are: Activities, Intents, Services, and Content Providers.

Activities - represents a user interface screen. Applications can define one or more activities to handle different phases of the program.

Intents - a mechanism for describing a specific action, such as "pick a photo". Everything has to go through Intents before creating activities or actions.

Services - a service is a task that runs in the background without the user's direct interaction, similar to a Unix daemon.

Content Providers - a set of data wrapped up in a common API to read and write it. This is the best way to share global data between applications.