Bluetooth PID controller for sous-vide

Greetings! I'd appreciate some guidance on the best way to approach this

Objective:
Create a PI/PID controlled sous-vide machine with a bluetooth interface on Android.

Hardware

  • HC-05 bluetooth module
  • 20 amp SSR controlling a heating element
  • atmega 328 with arduino bootloader
  • HTC One S android phone

Processing interface
I'd like a graph (similar to the PID front end) that displays my process value and set point value.

Buttons to do the following:

  • turn the system on/off,
  • switch between P/PI/PID mode,
  • text fields to change the P,I,and D values for tuning.
  • Button to toggle circulation pump.

Data logging, stored as a csv or something similar would be pretty cool as well so I could mess around with the numbers in excel.

What I need help with.

I'm not terribly familiar with using arduino libraries. I've read through the PID libraries on the arduino.cc website, but any help on how to actually use the commands would be helpful.

Tutorials on how to program a graph, buttons, a text fields that update in processing, based on serial communication from the arduino.

Tutorials/information on how to port a processing sketch to run as an android app.

-2 way communication via bluetooth serial. I'm not sure how to send data from my phone (Via the processing interface) and have arduino change saved intergers.

Thanks for the help! I realize I will have to monkey around a lot with various tutorials. I am in no rush to have a finished prototype, I just want to learn processing and build something useful and cool.