If you can think of specific easy feature ideas I'm definitely interested in hearing them.
As for calorie counting -- my experience is that there are lots of very good full featured diet apps that do that kind of thing so I am hesitant to compete with them.
However I do have a very quick calculator type control I could add if we wanted some very basic manual calorie counting..
One thing that just sprang to mind while reading your last post is a "Eating Timer". Personally, I'm attending a weight management clinic and my dietitian has told me a number of times that one of the key things overweight people need to focus on is "resetting" their eating habits, which included retraining themselves to eat / chew / masticate at a slower rate, which can sometimes be a hard thing to remember to do.
With this in mind, I' wondering if you could possibly add some sort of timer feature that would help in this area..say a count down, similar to a stop watch, that shows you when it's time to stop chewing and swallow. I'm oversimplifying things here, but I'm guessing you get what I mean.
Anyway, it's just a thought and I know I would personally find it useful.