Just a quick heads up. Two examples, SerialCallResponseASCII.pde and SerialCallResponse.pde refer to Analogue 0 as A0 in the examples, so won't compile.
The line in both is: firstSensor = analogRead(A0)/4;
This needs changing to firstSensor = analogRead(0)/4;
Curiously both the examples then have the second analogue port referred to correctly only a couple of lines later.