To start working on android projects you need android SDK and an IDE. As long as you have android SDK and an IDE which can be configured to work with that SDK you are good to go. The two most used IDEs are Eclipse with ADT bundle which was officially supported IDE for long time. But since the inception of Android Studio it has replaced the eclipse as official IDE for android development. This entire series will assume the use of Android Studio for working for android project. Android Studio can be downloaded from Android Developer website via https://developer.android.com/sdk/index.html.