A disclaimer here is that my AW7 is still running watchOS 9 [I will be posting a "how did y'all cope with no more Dock?" post next week!], so I don't know if the new features in the hiking workout take more battery power under watchOS 10, but considering I hiked the AT with watchOS 8 only [no way was I going to do an iOS/watchOS upgrade on trail!
], and still use the AW7 on hikes with watchOS 9, hopefully these tips will help
- Display mode - Always On - turn it off!
- Keep your iPhone in Airplane Mode and Low Power Mode [both can be quickly accessed via buttons in Control Center, so when you do want to contact the outside world, you can quickly do so]
- If you have a cell model Watch [I don't], turn the cell radio/feature off
- I used a Focus mode I created called Hiking which turned nearly all push notices off [doesn't matter too much when the iPhone is in Airplane mode, but does help when you go online with the phone and don't want/need the notices on the Watch - each time the haptic engine taps/vibrates your wrist, the battery is used]
- Used the default Apple Workout app to track my hiking [workout type: hike]. There's lots of 3rd party apps which can do hiking workouts and often have more/fancy features, but in the end, the Apple Workout app, from my pre-thru hike testing, proved to be the most efficient on battery life, which was paramount for me]
- I did not use any Apple device for on trail music/podcast listening, so I am unsure how those apps would affect battery life; sadly under watchOS 9, there is no breakdown of what apps are using the most power
- I used my iPhone for map/water source/shuttle info via an app called FarOut, which I used in Airplane mode - it allows you to turn the GPS on and off to see your place on the map, but I would only use the GPS mode for a second or two to confirm my location [usually to see how much of a climb I still had, though ahead of most large climbs, I would glance at my Watch to know I was 3 miles up a 7 mile climb, but used the iPhone FarOut app to double check in hopes I might be a bit further up ]
- For day hikes, I use AllTrails and have offline maps there [and allow the app on my Watch to send push notices, as it has a great feature for tapping your wrist when you go off trail - something I did years ago in the Smokies, missing a turn and continuing on another trail for 2 miles before I realized I had missed the turn!]
- Pre-hike - go into the Settings app on the Watch and find the Battery section and see what your current capacity is. [Tap the section labeled Battery Health]
- Pre-hike - as soon as you have taken your Watch off the charger the day of your hike, put that always on display into "tap to display" - even before you get to the trailhead. Start your conversation measures the moment you unlock your Watch. Focus mode, display off.
- I regularly pulled 11-12 hour days, though I would pause the hike workout [and on rare occasions stop it, if I was taking an extended break, and start a new hike workout when that break was over]. I'm an app hoarder at times, on my iPhone, but on the Watch [and for the hike, on my iPhone too], I removed a lot of apps I would not need on the Watch. 3rd party apps I kept on - MyRadarPro, Drafts, Pedometer++, WaterMinder, and for day hikes post thru hike, AllTrails. In my Hiking Focus Mode I allowed Weather, MyRadarPro, and WaterMinder to give me push notices [WaterMinder gives local push notices - the weather apps are useful when you have your iPhone on, warning you of lightning coming, etc], and post thru hike, definitely allow AllTrails to tap your wrist
I'd suspect that your battery drain may come from music/podcasting, as that's something I don't do on Watch, but I have on a day hike or two with iPhone and Spotify for music and Overcast for podcasting; Spotify has drained my 13 mini quite quickly before when I listened to a ~10 song playlist in the backcountry on speaker [no bluetooth headphones]. My experience with audio listening while not in the car or at home is very, very limited as it's not something I usually do.
watchOS 10 has new features for the Hiking workout, which I am testing out on my AW series 6, as I just installed watchOS 10 on my older watch a few days ago [long story], so I haven't yet found if those new features cause more battery drain; I am still getting used to the OS features, as I have several issues I'm trying to find workarounds for, so I haven't hiked with version 10 just yet. Hopefully later this month I will.
I'd say to go a day with the display off [tap to view - quick access to that feature in Control Center - the Theatre Mode - theatre mask icons - will enable tap to view display], just in normal life and see if you get more battery life out of your watch that way. I tend to suspect the audio listening is probably the biggest drain, but that's just a guess on my part. I'm happy to answer any other questions you might have!