I received my Watch4 from Samsung on Aug. 13. At first I was surprised to see how small it was. I had ordered the Classic that is like my Watch3, Watch and Gear3 and expected it to be similar is size but a little smaller. Turns out I had ordered the smaller one by accident (did not realize the classic came in the smaller size).
Taking some getting used to but it fits my better and probably will give better readings because of not flopping around on my wrist so much. The screen is smaller that I would like and the biggest surprise was the battery. It is much smaller than on the larger model . That shows in performance. It is now 12 hours since 100 % and at 50% charge. The old Watch3 would often go all day until bedtime at be typically at 75 to 80% this far into the day.
ON NumberSync. The watch3 took about 2 months to get Numbersync working (many posts from me on this forum about that). I initialized the watch by skipping LTE activation because I could not reach AT&T (Ida hurricane issues) so had to wait. I finally went to a factory AT&T store and got the activation card and account transferred from the old watch3 to the watch4. I got the LTE activated fine.
THEN NUMBERSYNC went berserk when I tried to enable it. The watch directed me to the phone (a Samsung S21 5G). There a window was open asking me to accept a bunch of agreements. After that it was to go to a screen where I was to enter a code that was already displayed on the watch. But NO, instead it went to my account pages and displayed a bunch of advertising including offer to upgrade my one week old Watch4.
Relying on my similar experience with the Watch3 which turned out to be programing bug in the Wear application (which at that time neither, Samsung, Google or AT&T felt responsible for). After about two months I was able to make NumberSync work an that watch but only after I threatened to file a complaint with the US Federal Trade Commission for false and misleading advertising.
This time I gave it a couple of days for all parties to iron out any wrinkles and tried again using the same process that I tried many times on the Watch3. First Reset both the phone and watch (after backing up- where the watch back up data is a mystery it now appears that both Samsung and Google keep backups). Then after full reset configure the phone on my WiFi and then restore. Restore from backup. Then restore the watch from backup and before doing anything more, follow the prompt to add NumberSync. Same think append as before. I tried again and that time the phone did some strange things. It popped up a window asking my opinion of the web site. I GAVE IT TO THEM. Then a few hours later, I tried the NumberSync again and this time the phone went through a period of flashing screens then a small RED BOX appeared with in White An Update Has Just Been Applied. Trying again, NumberSync went smoothly and it has been working since.
I hope anybody who had problems with NumberSync and stayed with my story, finds this of help. Anyway it gets the matter off my chest.