Amazing!
It’s very useful for knowing the realistic tendency of your weight. It has by far the best interface from all the similar apps out there and you can back up your data if you want and restore them in any Apple device you want to. Tip: Don’t turn on “Advanced lag compensation” option. It’s a bad additional calculation over the original one trying to make up for a supposed existing flaw in it (which doesn’t exist), ending up making wrong weight predictions. It simply has no purpose to exist. Stick to the original calculation.