@ridwan I'd describe it as a more personalized, more actionable, and more forgiving version of the Apple Watch activity rings system. It encourages you to keep your fitness/exercise within a healthy range, but without always pushing you to do more, more, more. And when you are doing too much – based on your sleep and activity – suggests lower impact ways to stay active or just rest. (See mine below) There's more, like activity summaries, exercise plans, and insights, but that's the gist.

Screenshots of the gentler streak app suggesting lower impact activities after a spike in effort over time.