[Samsung Gear 2] seh6183:
I decided to document battery usage on my gear2 after initially running into some trouble with the battery. I bought 2 brand new gear2's and when they arrived, I connected one to my note 3, which has a custom rom, and the other to a s5, with a stock rom. I noticed right away that the gear connected to the note 3 was draning battery much faster. This is what I set out to troubleshoot.

First of all let me explain the issues I had between the note 3 and the gear2 that was causing the battery drain; these are likely due to my rom being custom. When I first attempted to pair the gear to the phone, it would say device not supported. To even get the gear paired I had to use titanium back to remove anything that was related to the gear manager or gear in general. I then reinstalled the latest gear manager apk from the samsung store. This did not go smoothly and I had to find some missing apks as well because the app kept crashing. I didn't document exactly how I got it working because I was just trying any and everything to get it working. I know for sure that I was missing samsungservice apk and that was causing the app to crash at one point.

Once I got it paired up, I noticed when I would boot the phone "sensor service stopped" would show up. Also, when I would open s health multiple "health service" and related services would say that they stopped. I had to remove each one of those services with titaniuim backup and then reinstall the latest s health and let s health reinstall the services I removed. Sounds complicated and most likely no one will even run into these issues, but I posted this just in case. Also, I left "sensor service" uninstalled and it doesn't appear that s health reinstalled it and everything is functioning without it as of right now.

As long as gear manager is functioning correctly and there are no error messages from s health and everything is updated, there should be no abnormal battery drain. The following are some scenarios that I documented to show what normal battery drain should look like.

First thing I did was charge the gear up to 100% and let it sit overnight, for 8 hours while I slept. I disabled bluetooth so it wasn't connected to the phone, I also went to recent apps and made sure all programs were closed and that all sensors were disabled; sleep, pedometer etc.. After 8 hours of this I lost a grand total of: 1%. I woke up with 99% battery after 8 hours.

Next night I charged to 100%, connected to the phone via bluetooth, and closed all apps again and made sure no sensors were active and turned of notifications. After 8 hours of sleeping I had lost 4%. I woke up at 96% battery remaining. So the idle drain of just the gear by itself while connectd to the phone via bluetooth is half a percent an hour. Not bad at all.

Next I wanted to test how Tizen behaved with its apps. I read that some were getting better battery life by closing all apps down when not in use. I wanted to test this. So I did the same exact thing from the previous night except I opened every possible app as well. So bluetooth connected, no sensors active, no notications, but I opened every possbile app to load them up in the recent apps (memory). My findings were exactly the same as when I closed all apps the night prior. I lost 4% after 8 hours. So don't close out any apps, it does nothing on Tizen.

I next wanted to test the heart rate monitor as it was the single reason I bought the watch to begin with. Results were impressive. I turned the continual heart rate monitor on, running mode under exercise, and monitored my heart rate for 30 minutes (the amount of time I usually run in the gym). I lost 2% in 30 minutes. Not bad at all!

Next I tested one of the newer features of the gear 2 which was its ability to store its own music and play it back via bluetooth. I hooked up some bluetooth headphones and played continual music for 30 minutes straight. I lost 6% in 30 minutes. Thats 12% an hour. A little more than I'm comfortable with and it doesn't even sync with google music. It works very well, but just drains battery too much. Much better to use the media controller and have the phone play all the music.

For the final test I wanted to do a day of what normal usage might be like. I had bluetooth connected all day, notifications enabled, motion enabled (wrist motion to turn screen on), brightness at 2, I sent/responded to 10 text messages, received 25 or more notifications, 4 short phone calls, didnt use any monitors at all (heart rate, sleep, pedometer). I didn't play any music either. Ended up with 72% battery at the end of the day. At that rate I could have gone for 3 and a half days without charging. NOT BAD AT ALL! My gear 1 would come nowhere near that number.

Anyway I hope this may be beneficial to people struggling with battery life or considering a gear2 purchase because Of battery life. I know for me personally, battery life is the reason I returned the gear 1.