1 - Starting Android Development

For android development you need to have several tools on your computer. JDK, Android SDK and an IDE. We are going to use Eclipse in tutorials and samples because it is an open source and mostly used IDE on the world even if I don't like it much. Also we are going to use Java SE Development Kit 6 (JDK) because Java SE 7 has some problems with older versions of Android SDK and some external libraries.

You can download JDK from here, Android SDK from here and Eclipse from here (download Eclipse IDE for Java and DSL Developers).

Java Deveopment Kit (JDK) 

If you are new with JDK you may have some trouble about installing it. After installation, you need to set environment variables on your computer and it is told here. If you think it is done open console (cmd) and type "java -version". It should print some information about the JDK on your computer if it is installed and the environment variables are set correctly.

Android Software Development Kit (SDK)

If you installed it correctly the android-sdk folder must be like this.

Folders and applications:

samples - Contains some android sample applications that you may look at when you develop something like one of them. Initially it is empty because you need to download a sdk for a version of android first (it will be told later).

tools - Contains some tools that you need to use later. (ddms, draw9patch, sqlite3 ... )

SDK Manager - Manager application that downloads Android SDK.

AVD Manager - Virtual Device manager that creates virtual devices if you are not going to test your application on a real device.

Eclipse

After you download eclipse you don't need to install it. It doesn't require installation. Just place the eclipse folder in suitable place (like C:\Program Files\eclipse ) and start eclipse.exe.

Firstly you need to set JDK configuration on Eclipse. You can look at how to configure JDK on Eclipse.

Then  install the Eclipse Android Development Kit (ADT) plugin as it is told here.

When you finish, click Window at the top menu on Eclipse then you'll see Android SDK and AVD Managers at the bottom. Clicking them will not do anything but opening the applications in the android-sdk. 

Now, you've installed all the tools that you need for android application development. In next page, downloading an android sdk for each android version will be told.