After trying a few apps, I have found MyFitnessPal and tracking what I eat has become my daily routine. The app makes it very easy, has a great database of foods and in my case, I can almost always choose from my food history with 1 tap.
I'm in the 9th week of my diet, which simply means burning 1000 kcal more a day than I consume. My results are similar to the one in the blog post - spare 7000kcal a week and lose 1 kg.
Sure, measuring calories is imprecise at best, but my results speak another language.
The fitbit app sucks, it isn't well thought out and has numerous UI bugs. I had the fitbit one step tracker for a while until I lost it. Now I'm using my iPhone as step tracker, as I'm almost always carrying it in my pocket.