Hello Yoshihir0. I am Faiz, from Samsung.
Please be advised that you may track your SmartTag only by using Samsung SmartThings app at the moment. The Samsung Galaxy SmartTag and SmartTag+ are compatible with Galaxy phones and tablets using the latest version of the SmartThings app.
Nevertheless, we will take your inquiry as feedback for further product enhancement and improvement.
i just installed SmartThings App version 1.1.08.13 on my Galaxy SmartWatch 4 (One UI Watch version 4.5, software version R870XXU1GVK7 (SM-870NZSADBT) released 13 Dec 22, system version 11, WearOS version 3.5, Wear core services version 18.104.22.1686321169). Opening the watch app and clicking on my Smart Tag (model EI-T5300M, Firmware: 01.02.07; smart tag version 0.5.3; controller version 1.2.25-5) says "Faiied to Sync Data. Try Again.