Leadership, Software Development, Tech Industry, &c

My Android Wear Battery Drain Story

Last Friday, my LG G Watch informed me a system update was ready to install.  Eager to get Android Wear 5.0.1, and having already applied two updates to the watch with no issues, I installed it immediately.  After a minor hiccup, the update was apparently successful, but then both the watch and my phone begun experiencing battery drain.   A factory reset on the watch fixed it, but I only found out what was really going on by serendipity; here’s the story, in case it’s useful to someone else.

The Lollipop Update

That Friday afternoon, the watch reported 46% battery left when the update started.  It restarted, ran the update process rather smoothly, and then restarted again.  Suddenly, the watch goes dead mid-boot.  It was also very hot to the touch.  I took it off, let it cool down for a while, and tried to turn it back on using a paper clip on its reset pin.

It didn’t turn on.  The charger was home, so I had to wait a couple hours to try a different way to boot it.  Occam’s Razor suggested the battery was drained dead by the update process; and indeed, when placed in its charger hours later, the watch booted immediately (reporting 6% battery charge), the post-boot upgrade process finished successfully, and the watch showed both the new version’s number and features.

The Battery Drain

On Saturday, around noon, I noticed the watch was draining battery way faster than usual – about 10% an hour, when typically it does 3-4% an hour.  I rebooted it, and it seemed to stabilize.  I then noticed my phone was slightly warm, and its battery was about 10% below what I expected.

I had updated the Android Wear companion app on Thursday.  Had Google botched the app update?  The watch OS update?  On Saturday evening, the watch complained of not having enough storage left to download a new update.  “Bingo!,” I thought.  “Google indeed botched the update and there’s a new build available to fix it.”  But how on Earth was it failing due to low storage?  I had copied exactly zero files to the watch.  Surely something else was going on.

The Factory Reset

Sunday through Tuesday things remained the same: battery drain on both devices, missed attempts to download a system update, and having to reboot the watch to make it to the end of the day.  This is bad enough if you’re hacking a custom ROM on your phone, but having this on a device that consistently hits 35-40 hours on a single charge, running a stock ROM, was both intriguing and insulting – especially when your searches seem to imply no one else is experiencing the same issue.

On Wednesday, after running out of experiments to try, I decided to take the final step: perform a factory reset on the watch.  I had been pondering the impact, and just as planned, it was a very uneventful affair: the watch was back to its brand-new state, had to be paired to the phone again, and shortly thereafter was essentially in the same state as 10 minutes ago.  The battery drain had stopped, but I wasn’t sure if the issue was fixed or it was just a matter of the watch rebooting as part of the reset process.

Was That It?

Two things reassured me that everything was normal again.  First, manually checking for updates now had the watch reporting it was up to date.  I had googled Android Wear Lollipop OTA updates and learned the Moto 360 had got two in short succession, but indeed my watch model was running the latest version available.  Second, after the initial update I had two entries for Google Fit in Android Wear Mini Launcher, one with an icon, another without; the reset left only one, with its corresponding icon.

So probably that was it.  I figured something got messed up when the initial boot crashed after the update, excessively straining the Bluetooth connection between both devices and consequently draining their batteries.

But then, at 7 PM the phone announced it had to update 11 apps.  I normally don’t hesitate to do this over cellular, but this time I checked data usage first.  Lo and behold: 0.66 GB in about 7 days, way more than I usually burn.  I tapped for details, and Android Wear had used 377 MB up to that point.  Surely I wasn’t doing that many voice searches when out and about!

Everything has been normal ever since.   Apparently the system went into a state where it thought it had to re-download and install the update and kept doing that all the time, failing to actually install anything (the manual update check sort of “force closed” every time I tried to use it before the factory reset).  In the process, it not only drained both devices' batteries, but also hit my data plan a lot harder than it should.

What Is The Take-Away?

When something’s not right with an Android Wear watch, do not hesitate to factory reset it.  Most of the tweaks and settings are actually in the companion app, which is not affected by the process.  The watch can very quickly be brought back to its former configuration, and you’ll rest assured there are no leftover data issues causing a misbehavior.

Happy Wear-able computing!