According to the book, p. 357:
“Build and run the application again. Take a photo for an item, exit the application,and then press the Home button.Launch the application again. Selecting that same item will show all its saved details-including the photo you just took.”
Shouldn’t the order be: take a photo, press the Home button, and THEN exit the application? If you exit the app without pressing the Home button, the photo won’t be saved because the app does not enter background.