There are a ton of diets (and diet apps) in the world, and none of them actually work. The only thing that will truly make you lose weight is to eat fewer calories than you burn every day. And to do that, you have to do math. Nobody wants that.
Now there will soon be …. the magical Healbe GoBe (?!?!) bracelet. It counts the calories you consume and burn by monitoring cellular glucose levels through your skin. All you have to do is show up.
It’s not yet a thing, but it may yet be available by this summer. Whether it works or not will no doubt be up to interpretation.