The picture we have chosen above is rather appropriate. While the LG G3 is definitely not lying down when it comes to the features and specifications race, there is one way in which the phone is taking a nap, but that actually helps it beat its competitors. Apparently, the phone uses its energy so efficiently it is actually beating all of the big competitors at the moment in battery life tests, and this is despite the monster specs, like the 2K QHD display.

In fact, it beat the next closest competitor, the Samsung Galaxy S5, by 30 mins in PhoneArena's "real world-like" battery usage tests. Here's a quote from PhoneArena describing these results further,

You read that right -- despite the numerous arguments (and concerns) that the G3's super pixel-dense, 1440 x 2560 (QHD) resolution display caused, it would seem that LG was quite serious when it said that the optimizations it has implemented in both the screen and battery would ensure an industry-leading endurance.

For example, the LTPS panel dynamically tweaks variables such as frame rate when viewing static images, in order to arrive at a lower power draw in the longer term. As far as the user-replaceable, 3000 mAh juicer is concerned, LG claims to have replaced a lot of metal on the inside with graphite, and to have also implemented further, unspecified battery optimizations.
On top of the long lasting battery, there is another optimization that LG has made to the G3. According to their testing, it also charges faster than many of its competitors. It's amazing to see just how far LG has been pushing their technological evolution in recent months/years. They are obviously very serious about gaining ground against Samsung and Apple.