int servoPin = A3;
Servo myServo;
int servoPos = 0;
void setup() {
  // attaches the servo on the A3 pin to the servo object
  myServo.attach( A3 );
   //Register our Particle to control the servo
   Particle.function("servo", servoControl);
  // Keep a cloud variable for the current position
  Particle.variable(  "servoPos" , &servoPos , INT );
}
void loop()
{
  delay(100);
}
int servoControl(String command)
{
    // Convert
   int newPos = command.toInt();
   // Make sure it is in the right range
   // And set the position
   servoPos = constrain( newPos, 0 , 180);
   // Set the servo
   myServo.write( servoPos );
   // done
   return 1;
}