It won't be available at launch, but I kind of want to do an app version of the book I'm writing in addition to the print and ebook editions. This is exactly the sort of thing that could benefit from interactive elements that shipping it as a program would enable. For example, you could enter data from the machine calibration exercises and be able to see the graphs as they'd appear had the batches been roasted on your machine. There are lots of little things like that to make the case.