Forage is a stupidly simple calorie journal. Theres just one page, with todays food & exercise register. If you know what youre eating and just want to keep track, Forage is a lightweight utility without any fluff.
There are a lot of fancy apps with nutrition advice and barcode scanning and exercise databases. Theyre probably much better for most people, but this is the tool I wanted (and it doesnt take 10 taps to enter things).
Note: Forage is just a tool. Only change your diet with medical advice.