This article shows you how to control an Arduino from your Android device. We will use USB connection. There are two ways to talk beetwen Arduino and Android: Android Debug Bridge (ADB) MicroBridge mode and Android Open Accessory Protocol. In this example we will consider a MicroBridge mode and will transfer data from Android device to the Arduino.
For Arduino programming we need Arduino IDE
For Android programming we need: Java SE Development Kit, Eclipse IDE, plugin Android Development Tools (ADT) for Eclipse and Android SDK.