control Arduino board using Android sensors and wifi?
Is it possible?  Yes, it's certainly possible.  You can read the sensor values from within an Android program. It's possible to get Android to communicate with the Arduino through the USB.  The Arduino can be programmed to respond to what it gets through the serial.

Is it easy? Well, that depends on how good you are at Android programming.

One good place to start might be the ArduinoFirmata-Android project.  Don't worry about programming the Arduino, just install Firmata on it.  Then it's all down to how you program the Android device.  The Arduino just becomes a peripheral to your phone.