The S Health app is supposed to be a central hub for all of your health and fitness tracking data so it's capable of playing nice with other apps and services to pull in their data and provide users with a one-stop destination for all of their health and fitness metrics. S Health has lacked support for some popular fitness services like Fitbit, Runkeeper, and Strava so far which is what makes it unappealing to even those who use Samsung smartphones and have this app pre-installed on their devices because it's not capable of pulling in data from their preferred services.
Samsung has quietly made amends. It has added support for Runkeeper, Fitbit, Strava, Misfit, Jawbone, and Microsoft Health to S Health but you will have to dig deeper in the app to find them. Instead of listing them under More > Partner apps like other compatible services, this latest crop of supported services is listed under More > Settings > Connected services. Most of these services will share both sleep and exercise data with S Health except Fitbit which only shares sleep and Strava which only shares exercise data. All you need to start pulling in data from these services in S Health is ensure that you're running version 4.8.0 or above of this app.