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Once again, I'm confused by LG. I'm not sure what it's up to with the battery life of its flagship phone, as while it's got some decent specs on board, it doesn't last long enough - especially compared to how good this brand can be on battery life.
Here's how the battery will last over the course of a day: Getting up, spending 10-15 minutes messing about on the phone before deciding that it's a terrible way to start the day and...you know what? Emails can wait...will lead to an 8-10% battery drain (with brightness set to auto).
Then a ride to the station, Bluetooth music streaming, for about 10 minutes. The 45 minute commute will mostly be watching a video or two, checking feeds and listening to music wirelessly again - I'll arrive at work with about 80% remaining at best.
However, this is where it gets annoying. Despite some days being less heavy, I'll still leave work with only 30-odd% left, with minimal interaction and the phone connected to Wi-Fi. If I stream YouTube videos or use it for gaming at lunch, there's a strong chance the charger will need to come out about 4PM to ensure there's enough juice to get me home as it will be below 15%.
Even with minimal use during the day, the LG G4 was always below 15% come bedtime, if not completely run out. While I appreciate that a lot of what I do could be construed heavier usage - email is always syncing, for instance - compared to something like the LG G2 the battery life simply isn't good enough.
The upshot is my confidence in the G4's battery is not high - it's about the same as the iPhone 6 and HTC One M9, but slightly better than the Samsung Galaxy S6.
The screen is again the big suck on the power, with all those pixels needing power and the brightness needing to be up a little higher to keep the display viewable at all times. On Android 5.1, the problems with the OS maintained - it's the Google Services and the OS taking the second and third biggest drain slots.
The large, high-res QHD screen makes sense as a reason to drain the battery, despite LG promising that the hexa-core processor should be less hungry and the GPU is smart enough to throttle less important actions.
The odd thing here is that our media battery test, where we stream a 90 minute HD video on full brightness, only saw a drop of 15% - which is a lot less than other phones on the market. The reason for this is pretty obvious: LG's good at switching off the unnecessary things in the background when you're watching a video, it's just the background syncing that hurts the power.
The Sony range is still the best for power management and once again confirmed that the need for a QHD screen doesn't come close to being enough of a sacrifice for better battery life.
And there's no inbuilt wireless charging, much to my wireless chagrin. If Samsung can chuck two types in the S6, then LG can put at least one standard in there - especially when there's so much wasted space under the cover.
Gareth has been part of the consumer technology world in a career spanning three decades. He started life as a staff writer on the fledgling TechRadar, and has grown with the site (primarily as phones, tablets and wearables editor) until becoming Global Editor in Chief in 2018. Gareth has written over 4,000 articles for TechRadar, has contributed expert insight to a number of other publications, chaired panels on zeitgeist technologies, presented at the Gadget Show Live as well as representing the brand on TV and radio for multiple channels including Sky, BBC, ITV and Al-Jazeera. Passionate about fitness, he can bore anyone rigid about stress management, sleep tracking, heart rate variance as well as bemoaning something about the latest iPhone, Galaxy or OLED TV.