A very nasty mm-qcamera-daemon process bug is making rounds at everyone who is on Android 4.4.2 KitKat. This bug heats up your phone and then drains your battery like anything. This process is one of the processes that control your camera and for some reason, it starts using around 50% of your CPU which causes the heating and drain your battery really quickly.
Google acknowledged the bug a few days ago after a very length issue tracker thread at Google Code and a fix is in the works — Android 4.4.3 KTU72B to be exact. They seem to be testing the update internally now which means it should be out very soon for the Nexus family of devices.
Some users have been able to get rid of the bug with a simple restart — but for some, this is a recurring thing that keeps on happening whenever an app is opened that uses the camera in one way or the other i.e. Skype, Snapchat etc. I have had the same issue on my Nexus 5, but not as often as others have reported back in the Google Code issue tracker thread.
HOW TO: Fix mm-qcamera-daemon Battery Draining Bug
Here are a few tips that have been proven to fix this mm-qcamera-daemon process for some time, even permanently for many users:
1. Restart Phone – As soon as you start feeling your phone getting heated up for no reason or experience a significant drop in your battery percentage, we’d recommend you to restart your phone at once before it completely kills your phone with no battery remaining. In most cases, this should fix the problem. You can quickly go over to Settings > Battery and check if this nasty process is showing up in your apps list.
2. Uninstall Camera Apps – Another fix is to uninstall any camera related apps that you have installed recently before the mm-qcamera-daemon process bug started showing up. In a quick search over the Internet, many users have found a fix to this bug by uninstalling Snapchat, Instagram or Skype etc. Obviously, not a permanent solution, but is enough to wait for the official fix in the meanwhile.
3. Android 4.4.3 – This is the last fix — wait for the new Android 4.4.3 update. Google has found a patch to this bug and is expected to release the KitKat update anytime now. but please note, Google has only promised to fix this for the Nexus family of devices. As for users on the official KitKat update on the Samsung Galaxy S4, Galaxy Note 3 etc. should contact their OEM for a quick fix. Samsung is known for their slow roll out of updates, but we hope they are quick enough to release the patch as soon as Google does it.