I took mine back yesterday... So far this one has been fine, you and I must have gotten the random bad ones. I will keep posted if mine starts to do that, but so far in 21 hours no reboots.
I've not had any undesired reboots, and I'm getting very good battery life. Sounds like something's wrong there.
I have the power saver on, and quad core control enabled, but Wifi is on all the time as is bluetooth and NFC, 63% brightness, 30 second screen timeout, GPS on.
Sitting here in a typical day at work, I'm at 60% having unplugged from the charger at about 7 AM. My EVO with the large extended battery would be begging for a charge by now.
The signal here is horrible, so I'm sure that the battery life would be much better somewhere else.
That seems to be a point that not a lot of people understand, the phone communicates with the towers fairly frequently, and the worse the signal gets, the faster you spend battery.
Putting my phone in my halliburton briefcase without going into airplane mode would quickly drain the battery.
Do the firmware update. Also, have you installed third-party ATK (Automatic Task Killers) Apps like android assistant and ES Task Managers will kill vital Android operations and will hog memory and force restarts along with laggy interfaced. I learn this by uninstalling these apps. I have noticed that the battery seems to last longer and the device does not heat up as much. Now I have no freezing or random reboots. I have also heard that if neither of the issues apply to you then it might be a micro sd issue and since we can't swap out the sd card you might have to take it in to get serviced or just get a replacement.
Side note: The battery on the Optimus G is a joke. 2100 mAh is suppose to last 12-13hours but I get about 6 hours. My EVO with a 1500 mAh battery lasts about the same. Take into consideration the bigger screen quad core processor and LG's UI but come on. I had the Apple iphone 5 before the Optimus G and I returned it because the battery was horrible and it had no data connection in my work area. But I guess having data should be enough I thought this phone would last a lot longer than my old EVO 4G but I am at 60% by mid afternoon. Unplugged from charger at 9am and by 12 the phone battery is about half done. I have auto dim, data, 30 second time out, ECO mode, and turn off sync to manual for my email. I have noticed that within the first hour the phone goes from 100% down to 80% with only checking the status of the phone and with no other operation. I am going to contact wirefly to see if I can get a replacement. Hopefully this fixes it and I have heard that if LG ever sends out the 4.1 or 4.2 Jellybean update it should help with battery consumption.
After a big to-do with the Sprint reseller I finally got my device replaced. I have not experienced any random reboots. I have however still been seeing some rather outrageous battery usage stats. I have a LG HBS-700 Bluetooth stereo headset and stream Pandora while at work. I literally watched the battery percentage drop about 1% per minute. Granted I had 6 apps running and all the bells and whistles on, but thats f'ing nuts! Even while it was plugged in its draw was more that it was taking. I disabled GPS (biggest help) and WiFi, I shutdown Pandora and am now using G-music and battery performance is far better. I'm using 'Elixer 2 Widgets' to keep an eye on the battery draw in mA. Its nice being able to see the negative mA while its charging. It will also show the battery temp and a bunch other stats. I've also decided to start using the LG Tag+ tags to change my phone services while in the office like disable GPS and WiFi, neither of wich I need while sitting at my desk. My Office tag also sets my sound profile to Vib only as not to disturb my neighbors. All this and enabling Eco mode it will be a waiting game to see how it all pans out. Will update after the holiday on standard use seeing as how I typically don't stream music anywhere but at the office.
I am having the same issue about 5 times a day ... today my phone also shut off and couldn't get it to turn back on for almost 10 minutes ... find it hard to believe there are this many "bad phones" ... mine was purchased in Boise, Idaho at a Sprint location ... I'm an over the road driver unable to get back to the store for another week or two ... gotta be a software issue because I'm reading a lot of people are having the same problems ...
Mine has been awesome since I traded for a new one. I love this phone, hopefully you can get in for a trade at some Sprint location before your I think 2 week period is up.