In October 2011, mobile research firm Research2Guidance reported that the number of apps available in the Android Market hit an all-time high of 500,000. While these apps may vary widely in purpose, they all have one thing in common. The apps were created using the same core set of tools from the Android development package. With the Android development package you can create your own apps for smartphones and tablets running on Android's operating system.
The Android development package includes numerous components including a software development kit or SDK. A SDK is a comprehensive set of tools for building apps. For Android apps, you initially download the SDK starter package that includes a few basic tools. Once you have the starter SDK installed, you can access an additional SDK with more tools as well as other components like the Android platform. The SDKs give you sample code, a debugger, documentation and emulator, along with other tools.
The Android development package can be installed on a Windows, Linux or Macintosh computer. To work with the various components and build the app, you can use either a text editor or an integrated development environment. An IDE provides a more comprehensive setup for building apps and allows you to perform many steps and tasks from a single workspace. Android recommends you use the Eclipse IDE, but other solutions will also work. Android apps are written in Java so you must also have that program installed on your computer.
Once you have set up your environment and downloaded the Android development package, you can begin building your app. Android apps have four pieces -- activities, services, content providers and broadcast receivers. These pieces work together to build the app. Activities are the face of your app. Each activity you build is made up of a single screen with a user interface. Your app will likely consist of multiple activities, but each acts independently. Services run in the background of the app and perform functions like fetching data. Content providers manage the app's data to determine what will be shared and what will remain private, and broadcast receivers respond to or initiate announcements. For example, you may build your app to broadcast a status bar notification when an update is available.
Publishing is the final stage of Android development. You can use the tools included with the development package to check for errors, test your app and prepare it for distribution. To have your app featured within the Android Market, you must first have a Google account and create accompanying promotional items like a description, screenshots and graphics. Google also requires that you sign your application with an electronic security key. Once you have your app uploaded, you can target specific audiences as well as manage and track its performance.
- Android: Android Developers; Android SDK
- Android: Android Developers; Introduction
- Android: Android Developers; Publishing Overview
- Android: Android Developers; Application Fundamentals
- Android: Android Developers; Publishing On Android Market
- PC Magazine: Report: Android Market Reaches 500,000 Apps
- Photo Credit Sean Gallup/Getty Images News/Getty Images