We all love Android, and we also love when Google releases a new iteration of our favorite mobile OS. Sometimes, though, even Google screws up a bit, and Android 4.2 is looking to be one of the most bug-ridden releases since Honeycomb. And, let's be honest: 4.2 isn't exactly the leap that 2.3 to 3.0 was, either. Chances are, if you're on Android 4.2, you've experienced at least one of the issues here. Some aren't that bad, but some can just ruin your day, and we're a little shocked Google missed them.
We'd love it if you could confirm whether these bugs happen on a device not listed as "known affected," or of any other serious issues you've been experiencing since the bump to 4.2 on your Nexus.
Known affected devices: Nexus 7, Nexus 10.
This bug isn't one I've experienced personally, but many, many others -including Artem - have. After the Android 4.2 update (or just on the Nexus 10, in general), auto-brightness behavior has been less than reliable, particularly on the Nexus 7 - though that device's problems aren't strictly limited to Android 4.2.
The issue specific to the Nexus 7 causes the screen to noticeably flicker when set to auto-brightness, and has been present on all Android builds, especially at low levels. With the Android 4.2 update, that behavior has apparently gotten worse. Yikes. Which leads us to the generic auto-brightness bug.
Auto-brightness in Android 4.2 seems to randomly adjust with no changes in ambient lighting, as though the sensitivity is too high, or some sort of other software glitch is causing the brightness setting to suddenly drop, then come back up to the appropriate level. Basically, auto-brightness is borked. While I never found auto-brightness on the Nexus 7 was good in the first place, many are now complaining it is much worse, and on the Nexus 10, as well.
Bluetooth Is Basically Broken
Known affected devices: Nexus 10, Nexus 7, Galaxy Nexus.
We've already received numerous emails about this issue, and I've confirmed it myself: Bluetooth on everything but the Nexus 4 (apparently) is in an absolutely sorry state right now. Audio streams extremely choppily, sounds mediocre, and often loses connectivity entirely. 3rd party Bluetooth apps that create compatibility with devices like the Sixaxis or Wii controllers no longer function at all, and throw an error instead.
This is bad. This is the kind of thing that makes someone return a phone or tablet, because A.) people have no patience for stuff like this, and B.) there's zero reason something as simple as Bluetooth should be broken so badly out of the box. Google needs to mark this one "critical" and fix it ASAP.
Random Reboots / Major Instability
Known affected devices: Nexus 10, Nexus 7, Galaxy Nexus, Nexus 4.
File this one under "critical," as well. I myself have experienced this bug - my Nexus 7 rebooted no less than 4 times this weekend, several when it was just sitting idle with the display off. That's... bad. I've since done a factory reset, and in the last hour, so far so good. You'd think a problem this serious would be limited to a pretty specific subset of hardware, but no -
everything but the Nexus 4 is affected (which seems to be the case for every one some of these bugs, oddly) all Nexus devices appear to be affected (thanks for the input about the Nexus 4, guys). The reboots occur when opening webpages in Chrome, using Play Magazines, and a variety of other circumstances (like doing nothing at all).
Nexus 10 users are apparently the most-irked when it comes to the reboot issues, with them often occurring multiple times a day. The behavior described sounds a lot like a kernel panic - total system lockup while in the middle of a task, followed by a soft reset. Video playback seems to be one suspect for these lock-ups across all affected devices, with the YouTube app having been cited several times in various postings.
The reboots aren't the only problem, though. On Galaxy Nexuses and Nexus 7's (eg, devices upgraded from Android 4.1.2), performance has taken a complete nosedive. Opening apps, Google Now, or navigating through the UI has become much slower in some cases. I noticed this when I upgraded, too - all that butteryness suddenly got a little less smooth. However, after a factory reset, I noticed marked speed improvements in the UI generally. Personally, this is where I immediately go if I'm having performance problems (and haven't recently installed a new app). There's no use in complaining about it if you haven't tried it already, because that's just what Google's going to tell everyone to do eventually.
However, many posters in various Android bug threads are reporting that factory resets don't alleviate any of these issues - which is highly concerning.
The stability problems don't end there. Galaxy Nexus owners are saying that their phones' displays are randomly turning on without any interaction. The system clock's time is off by anywhere from 3 to 10 minutes when set to "Network Time" for some. Apps are force closing for no apparent reason. For an incremental update, Android 4.2 sure seems to be causing all the problems associated with a much more significant OS release.
Extreme Battery Drain / Slow Charging
Known affected devices: Galaxy Nexus, Nexus 7, Nexus 4.
This is really two separate issues, but they both fall under the "my battery makes me hate my life" umbrella, so I'm lumping them together.
The first one is battery drain. I (and others) have noticed Google Play Services has absolutely eaten into my Nexus 7's battery life post-Android 4.2. Usually, I get a solid 3-5 days of standby time if my Nexus 7 is sitting mostly idle, but after leaving it alone this weekend for under 48 hours, I returned to it at about 8% remaining. Not good. Similar issues have been brought up by Galaxy Nexus owners. In addition to that, exchange accounts are apparently causing massive loss in battery longevity. The exchange issue can be alleviated by removing and re-adding your accounts, according to some of the bug threads.
The Google Play Services problem, though, doesn't seem to have a solution presently, and reportedly is affecting all Nexuses. I'm also hearing from numerous people that NFC is causing extreme battery drain in some cases across all Nexus devices, a problem I, too, have experienced.
The second issue - slow charging - is specific to the Nexus 7. For now, there seems only to be an XDA thread acknowledging its existence, but both Artem and Cameron have been able to replicate it on their own devices since the update. The issue is quite simple: the Nexus 7 charges really, really slowly. It happens intermittently - sometimes it will charge quickly, sometimes not. Which to me suggests some kind of issue with the operating system recognizing the amperage of the charger, and going into "slow charge" mode (eg, over USB) at 0.5A when it should be at 2A (standard USB wall charger).
Lockscreen Widgets / Camera App
Known affected devices: All Nexuses.
The newly-implemented lockscreen widgets have gotten off to a bumpy start, with numerous bugs and glitches affecting them across all devices. Lockscreen music controls for Google Music are randomly disappearing if a 3rd party music app is started, stopped, and then Google Music is started again, not reappearing until the device is rebooted. And the widget, if the system decides to kill the music app the widget is linked to, causes very strange behavior to start occurring on the lockscreen.
The camera app also has a minor problem when rotating from portrait to landscape mode, taking up to 3 seconds to rotate depending on the device. Instead of simply rotating the button arrangement, the entire display rotates, causing substantial lag in the app.
These last ones are quite minor, but they're generating quite a lot of complaints at the moment.
December Is Missing!
Known affected devices: All Nexuses
It looks like in its haste to finalize 4.2, Google forgot something pretty major in the People/Contacts app: December. Yes, they omitted an entire month. Oops.
Any other weird happenings in Android 4.2 that you've found? We've intentionally skipped over some of the smaller ones, but feel free to chime in about anything you've discovered - particularly if one of the issues above is affecting a device not listed (stock Nexus devices only - custom ROMs just add too many variables).