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Here's where the OnePlus X starts to fall down. OnePlus has opted for an older chipset than in the OnePlus 2, installing the Qualcomm Snapdragon 801 in the OnePlus X.
While it's an older chipset it should still be capable of impressive things – this is what powered the stellar HTC One M8 after all. But I've encountered performance issues with the OnePlus X.
I've found that some intensive activities have proved a struggle for the OnePlus X. Among other things, video could lag quite a bit, meaning that I was missing seconds of small clips – and it wasn't just when streaming.
I had a video clip on the phone for battery testing, and while running that test I saw the video freeze a few times. A phone with these specs should really be capable of making it through a video without stammering.
I've put the OnePlus X through some intensive gaming tests as well. I played the graphically intensive Asphalt 8 racing game on the OnePlus X and it handled itself pretty well to start with, but buckled under the pressure after a while.
I found the game stutter at some moments, and whenever something graphically complex was happening on the screen it really struggled, especially if I was trying to play music from Spotify at the same time.
You can't really expect silky smooth gaming performance from this kind of processor, but I am a little disappointed with the performance of the OnePlus X.
At least the OnePlus X didn't heat up while I was gaming, however – unlike with the last phone I tested, the Sony Xperia Z5.
Running the GeekBench 3 bench marking software, the OnePlus X came out with a single-core result of 909 and a multi-core score of 2408.
To put that into context the OnePlus 2 scored 4795 on the same multi-core test. The iPhone 6 scored 2905, however, so the OnePlus X isn't that far off the pace.
Overall, though, I expected better from the OnePlus X. It's far from unusable, but I'd hoped for a slightly more in terms of performance.
Battery
Battery performance on the OnePlus X is nothing to write home about – if anything it's a little disappointing.
I've haven't made it to the end of the day with anything over 30% left in the tank, and that's even on days when I wasn't using the phone much – and when the screen was on for much of one particular morning I found myself down to 40% battery before lunch.
It charges quickly enough, but it would have been nice to see OnePlus include fast charging – once you've used fast charging on a phone it's difficult to go back to the 'regular' version.
Like other OnePlus devices it's also missing wireless charging – although at least it's understandable that this technology hasn't made it into the OnePlus X, whereas it's annoying that it's not included in the 'flagship-killing' OnePlus 2.
The battery is also non-removable. Manufacturers are increasingly going with fixed batteries, and it doesn't seem to bother too many people, but the absence of fast charging becomes more of an issue given that you can't hot-swap the battery in an emergency.
I ran the traditional techradar video test on the OnePlus X, which confirmed that the battery is nothing special. This involves playing a 90-minute video, with the screen at full brightness and enabling all the connectivity options, and seeing how much battery is left at the end.
The OnePlus X had 73% left, which is the exact same score as the OnePlus 2 – and that's quite a shock when you consider that the OnePlus 2 has a 3,300mAh battery, while the OnePlus X only has a 2,525mAh pack.
Still, that's a drop of 27%, which isn't a particularly good showing. The OnePlus One only registered a drop of 17%, while flagship phones with 2K displays, like the Galaxy S6, have come out with scores around the 15% mark.
I personally watch a lot of video at around 60% brightness to try and save on battery, so I ran the test again at 60% brightness and the OnePlus X came through with 79% battery remaining – that's not a massive improvement, given how much less was being asked of the battery.
James is the Editor-in-Chief at Android Police. Previously, he was Senior Phones Editor for TechRadar, and he has covered smartphones and the mobile space for the best part of a decade bringing you news on all the big announcements from top manufacturers making mobile phones and other portable gadgets. James is often testing out and reviewing the latest and greatest mobile phones, smartwatches, tablets, virtual reality headsets, fitness trackers and more. He once fell over.