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The HTC One M9 is a very good phone, mostly let down by the fact the one from last year was brilliant. The only reason it's judged so harshly is the fact that it's got so many other brilliant phones to steal its thunder - so if you're looking for an alternative, these are the ones to look at.
Samsung Galaxy S6
The Galaxy S6 is definitely the phone of this era that most HTC users will be thinking about instead, especially if they're into the Android ecosystem.
While HTC managed to reboot its ailing flagship franchise three years ago, it took Samsung until 2015 to manage the same thing - and boy, has it done it. The Samsung Galaxy S7 represents a further refinement, but the Galaxy S6 can be picked up for around the same price as the HTC One M9, and it's still a strong performer.
There's nothing particularly outstanding about the S6, but it manages to do everything very well. The camera is feature-packed and offers up brilliant snaps, with a more-than-decent 16MP low-light sensor. The processor is an Exynos 7420, built in-house and hyper-powerful, and the QHD screen really adds clarity to the mix.
However, that's likely more to do with the Super AMOLED technology underpinning than the crystal clear resolution on offer - after all, there's only so much sharpness the human eye can discern. It doesn't stop images looking amazing on it though.
The main issues you'll have to deal with are poor battery life - with a smaller battery pack and higher res screen, it's understandable that this would be slightly shorter in the power department.
OnePlus 3
All of the other alternative picks we discuss here are of a similar age or even older than the HTC One M9. The OnePlus 3 is a good year fresher, with a larger and more vibrant 5.5-inch AMOLED display and a significantly faster Snapdragon 820 CPU with an unusually high 6GB of RAM.
It also has a similarly accomplished - if not quite as flashy or refined - all-metal design, and the OnePlus 3 also has the advantage of a fingerprint sensor for speedy and secure access. Its camera is similarly competitive, too, whilst hardly being outstanding.
Despite all this, the OnePlus 3 costs £329/US$399 (around AU$450) brand new. It's difficult to justify the purchase of a less current and generally inferior phone for similar money.
HTC One M8
And we come to my biggest issue, that the predecessor to the One M9 is actually a little bit better.
While it does lack in terms of spec, it manages to more than make up for it in cost, coming in between half and two thirds the price of the One M9.
And I can't really say what's that much worse with it. The battery life is actually a touch better, the build quality not miles away and the camera not terrible in comparison. OK, the new 20.7MP camera on the One M9 is stronger, but it doesn't have the innovative Duo Camera sensor for really cool effects.
The Sense experience from the One M9 has made its way to this device with Android 6.0 too - so really, with the same screen, a more palatable price and a little longer in the battery, is this actually the better phone?
HTC One A9
HTC released another interesting phone in between the One M9 and the HTC 10, and it's called the One A9. Many have criticized HTC for mimicking Apple on the design of this phone, but we still think it's a great looking handset that stops people in their tracks.
It comes with Android 6.0 Marshmallow on it, which the HTC One M9 has only belatedly caught up with. But the battery isn't all that powerful on the HTC One A9 so it may be worth going for the One M9 if you're a heavy user.
There's also a great 13MP camera on the back of the HTC One A9 that takes just as good images as the HTC One M9, if not better. If you're looking for something from HTC, it's certainly worth checking out the One A9 before you just decide on the One M9 - though you may need to shop around online to find one.
LG G4
The LG range is always going to be a thorn in HTC's side, as it can offer a premium smartphone experience for a lower price, as it channels its marketing budget back into the phone's cost.
The QHD screen is the real talking point here, but it doesn't really offer that much more than HTC does, and the build quality of the M9 far outstrips the weird leather the G4 is packing.
For the price - you can grab the LG G4 for less than £300/US$300/AU$450 now - it's a tough call. If you're not fussed about design, the G4 is cheaper and faster with a better screen and camera (although not as much power) - but it does have a leather back, for some reason.
Sony Xperia Z5
Sony's Xperia Z5 is a big improvement upon the phones that have gone before. This time there's a new luxurious design with frosted glass on the back and then there are metal edges for the first time.
There's a new fingerprint sensor on the side and considering this is the first time Sony has managed to integrate one into the phone, it works surprisingly well.
There's no wireless charging here, but the Xperia Z5 has some of the best battery life we've seen on an Android flagship phone for quite some time.
And then there's the camera. It includes a 23MP sensor with a new autofocus mode that means you're able to take snaps of fast moving objects and catch the action. It's a big upgrade from Sony and is a serious competitor to the HTC One M9.
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.