I realise the article is about “full featured” smart watches which I guess means touchscreen in some way, but I think any article that talks smartwatch and battery life should mention the Withings Nova or Scanwatch. Heart rate, ecg, spo2, sleep tracking, temperature tracking, phone notifications, etc. I mean this thing does it all but has a “classic” watch form factor and having owned the nova; the battery life is WEEKS not days. I honestly forget about charging it entirely until it reminds me in anywhere from 3-4weeks (or longer if I haven’t been using the workout function daily).
Honestly. Will never go back to a “smart” watch while the “semi-smart” Withings gives me everything I need with this type of battery life.