MyFitnessPal, one of our favourite fitness and nutrition tracking tool, has always offered a free version. The service just added a new premium account tier with more discrete options for your goals, more ways to keep track of the macronutrients in the foods you eat, diet and meal suggestions, and -- of course -- no ads.
Existing ree users won't notice a difference now that there's a premium version kicking around (aside from being prompted to upgrade). The premium version lets you, for example, track your protein intake, carbohydrates or fat intake over the past several days or weeks, which is useful if you're trying to hit a certain level. You can even "quick add" by macros, so if you need 20 grams of protein, you can specify that and the app will show you what to eat to get it without breaking your other goals.
The premium version will also suggest foods to help you get to your macro goals, so if you're trying to slowly cut back on sodium, you can use MyFitnessPal to see how the foods you eat rank when it comes to sodium. This makes it easy to see your worst offenders. Premium users will also be able to set their macro and calorie goals on a day-by-day basis, so if you have different numbers for a workout day versus a rest day, or have a "free day" in your diet, you can account for it easily.
All of those features come at a price though -- premium accounts cost $US10/month or $US50/year. You can sign up and read more at the link below.