As noted by many users Galaxy watch 4 series have some battery life issues. I'm trying to figure out root cause (with limited tools, not much help from Wearapp's battery menu). I did some tests on GW4 44mm BT2 model. 2-4% per hour battery drain when watch is idle is too much for a smart watch really. Even when airplane and power saving modes enabled at the same time (no BT, no Wifi, no AOD, no SPO2, screen brigtness on 15%, only 10 mins heart rate on (runs once or twice an hour), sleep tracking and workout detection is on) while watch is idle in this state without any screen activity it drains battery around 1.2-1.5% per hour during day and around 1.5-2% over night during sleep. All this suggests something in the background drain battery fast. Battery menu on wear app doesnt give much clue since list of apps there (samsung health services, screen activity, ui etc.) all combined shows only about 1/3 of total battery drain. So what does drain battery the most, about remaining 2/3 of total battery drain, when watch is idle? Is it WearOS itself? Is there a tool application that shows more battery info than Samsung's Wear app, like Gsam battery on phones?
I think most likely root cause of battery drains are software based, Wearos and/or Samsung side, and they can be improved by devs. For instance; maybe some process/services (wifi, BT, notifications, gps, google services, health services etc. ) are running too frequently in the background which use cpu/memory power even if sensors/features are disabled and watch is inactive. There might be bugs and/or just bad implementations. No matter what, they should be found and solved by WearOS/Samsung devs. Maybe solution is as simple as changing the frequency of one service/process call that cause the most battery drain. Letting users change/tweak those settings that affect battery life would be better idea in fact.
27% in 11 hours makes about 2.45% per hour which is still bad if watch had been inactive/idle mostly. There are much cheaper watches and fitness bands gives like 2-3weeks battery life with continuous step tracking, occasional heart rate tracking, showing notifications from phone, occasional workouts etc. They have worse battery capacity than GW4 but are running on proprietary lite OS. WearOS is not battery optimised OS yet but can be optimised and can also provide a lite mode (like fitness band mode) which would reduce battery consumption drastically, if some good developers work on WearOS and Samsung softwares. Hope that they will optimise the OS soon, GW4s have good hardware, its very sad software **bleep**.