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What can you expect from a smartphone that has a 3,500 mAh battery and an incredibly powerful processor? Near bliss. That is, if you can live with the gigantic, curved 720p display.
First, let's get battery performance out of the way. We loved the LG G2's battery life, and it had only a 3,200 mAh unit powering a much higher resolution display.
The LG G Flex easily went two to three days on a single charge, just as LG promised. I spent a lot of that time with push notifications enabled for nearly every app that would support it, watching videos, listening to music and playing graphically intensive games for longer than we'd like to admit. But for the sake of this review, I will admit that I spent about an hour and a half one night playing Asphalt 8.
I also ran our HD test video at full brightness and sound for 90 minutes. Starting at 100%, the G Flex went down to just 87% after 90 straight minutes of our Gareth Nyan Cat HD video, which is impressive.
However, I'll always recommend charging opportunistically, or charging whenever you can, simply because it's a good habit to have and it won't damage your battery.
But if you don't care for plugging in at every opportunity you get, you'll have few worries when it comes to the G Flex. Unplug it in the morning and you'll still have juice until about late afternoon or so the next day, unless you're really pushing it.
Performance
Raw performance on the G Flex is great. We're cautious about running benchmark tests these days because manufacturers are now gaming and cheating these benchmark tests so that they produce inflated results.
What matters is how your phone performs in day to day use, and after battering the phone with tasks and games and videos for over a week, we can confidently say that you won't be disappointed with its performance.
There was never a glitch, lag or blip anywhere in the phone's apps or services, and yet given its power, the battery held up like a champ.
We can all thank the 2.26GHz Snapdragon 800 and its 2GB RAM, which is more than plenty for most of the things you'll need to do on this phone.