2 and half days if lightly used. Moderate usage with continuous heart tracking is 1 and half days to 2 days. With the Always on display you will be charging everyday.
But it's not really a true smartwatch as it is limited in 3rd party apps. It's like the dumb phones of old with limited functionality. Unless you are fine with that, it's cool
Yes you can't install other apps, Samsung watches are better but the problem is battery life 🙌 imagine changing your watch everyday or after 2 days 🙌. So it depends on what you like.