So glad your Dad continues to do well and that the iPhone is helping. Maybe he could use his iPhone to list what different things taste like and from which part of the tongue the taste comes from. He could use the "Notes" app. I was always amazed at all the different tastes that popped up when my son was experiencing Rad Tx. Does he play Scrabble? There an app for that and the iPhone version comes with a little Smiley face that tells you if you played a really good word or if not, it will tell you what you should have played. Your Dad sounds like a fighter! And that is so encouraging for you, too!