This is almost exactly an idea I've been kicking about for years. I'm very hopeful for where this will go. It looks great and seems very easy to use. Also love that it doesn't ask for any unnecessary permissions.
One suggestion that I could use right now... the ability to delete data / undo adding data. I added a bunch of stuff just to play with it and now it doesn't accurately reflect what I've eaten.
Also, how often should I update? Just every day? At the minute when I eat the food?