The previous model Samsung watches had an operating system called Tizen, and the 4 has an android based system. There are two ways to get Dexcom readings on your watch. The first uses an app called Tasker. You have to buy the app and download the script from FreDiabetes GitHub site, then follow instructions. It is described in this thread:
Xdrip+ - Watchfaces/ BG-Values on your Tizen OS Smartwatch (all samsung smartwatches) and on your Android Wear OS watch
It is simpler than it sounds.
The second method, he refers to allows you to either download one of his designs, or make your own to suit your needs. It is all graphical. Here are three watch faces I created using the method he described, but I added color ranges to BG values (again using his programing).
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