When watchOS 10 first came out my watch updated automatically. I’m one of the unlucky few whose watch started using too much power. Using extra power after a major update is common for a couple days. After two weeks, my watch still had to be recharged several times per day (not acceptable). This was not an issue with watchOS 9.6.3 (there is no way to go back).
I have some draconian steps and a configuration that gets my watch through a day on one 90 minute charge, but NOT back to pre-watchOS10. My settings remove or disable much of what makes an Apple Watch special…but it’s better than a frequently dead watch.
As a side note, Apple Technical Support has been consulted twice: online and in-person at an Apple Store Genius Bar. Diagnostics pass, my watch has never been wet, and my S4 is not covered by a warranty.
Apple Tech Support is aware of the problems and tried to solve my issue but ultimately provided two options:
1) trade in my watch for a new S9 (net cost $400) or
2) replace the battery even though it has 84% capacity ($299 cost for battery capacity over 80%, $99 replacement battery capacity less than 80%).
Neither option seems all that great…yet.
Here are some tricks and tips that might increase an Apple Watch’s daily battery use with the current watchOS 10:
- Adjust display settings. The display is one of the biggest battery drains, on S4 through S6. Reduce display impact by adjusting the brightness, reducing the amount of time the display stays on, and disabling the always-on display for S7 and newer.
- Reduce the number of notifications. Every notification that appears on the screen requires the watch to wake up and use battery power. Try disabling notifications for apps that you don't use often and/or try setting notifications to silent delivery.
- Turn off haptics. Every time the watch has to send a haptic, a small vibrator has to use battery power.
- Remove apps from the Smart Stack. While this is a new feature, on my S4 it seems to consume significant power.
- Delete 3rd party apps. Some 3rd party apps are not behaving well with watchOS 10. Delete the 3rd party apps on the watch AND on the iPhone.
- Disable location services, especially for the Apple weather app. Apparently the weather app frequently checks location and retrieves weather for the location, even if your location is not significantly changing. Remove all but one weather app location. Completely removing the weather app may help too.
- Turn off background app refresh. Complications will still update in the active watch face. Other apps will refresh when you open them or a watch face with corresponding complication.
- Turn off as many features as possible. Many Apple Watch features use battery power, even when not actively using them. For example, the heart rate sensor, GPS, and Wi-Fi can use battery power. Try turning off these features to save battery life.
- Use Power Saving Mode. This mode disables certain features to extend battery life.
Here are some additional tips that may help improve battery life on watchOS 10:
- Unpair and re-pair Apple Watch. This can sometimes resolve battery life issues.
- Restore Apple Watch from a backup. This can also help to resolve battery life issues.
- Reset Apple Watch and do not restore from a backup. This can also help to resolve battery life issues.
If these fail to help with the short battery life:
- Contact Apple Support. If you're still having trouble with battery life, contact Apple Support for assistance. Do not expect good technical support from these Apple Community Forums, there are a few trolls who generally make condescending and smug remarks.
If you are not happy with watchOS 10, share your concerns directly with Apple at Feedback - Watch - Apple
Hope this helps your situation!