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HTC One M8
The HTC One M8 is no longer the "best mobile phone in the world", but it was the phone to beat in 2014 and gave the Z2 a run for its money.
Does the Sony Xperia Z2 topple the M8? Honestly, no. As a complete package the One M8 wins out, but the Z2 still has a couple of things over its Taiwanese rival.
A lot has been said about the camera on the M8, and in a straight spec shootout the Xperia Z2 beats it hands down with a 20.7MP snapper versus a lowly 4MP offering.
The Z2 camera doesn't bring anything particularly new to the table though, while the M8 has the innovative Duo Camera setup and a much faster image processing time.
4K video recording is just a distant dream with the HTC, while the Xperia Z2 can pull out some of the best footage you'll see shot on a smartphone.
When it comes to interface, performance and design however the One M8 offers up the better experience. If the camera isn't a huge deal breaker for you then the M8 is the better option, but if you fancy a reliable snapper the Z2 is the way to go.
- Read our HTC One M8 review
Samsung Galaxy S5
The Samsung Galaxy S5 was another stong contender in 2014, and independent screen testing firm DisplayMate said it had the best display it has ever tested.
Things look good in the Samsung camp, with a fingerprint scanner and heart rate monitor in the S5 helping it stand out from the crowd.
While Samsung may well have packed a whole heap of tech into the Galaxy S5 a compromise had to be made somewhere. Build quality.
The Galaxy S5 is undoubtedly plastic, and it severely lacks the premium appeal of the Xperia Z2. Both handsets are waterproof, so it's not like the S5 can use that as an argument. It's features versus form here, which one is more important to you?
- Read our Samsung Galaxy S5 review
Sony Xperia Z3
Naturally, there's a degree of competition between the Sony Xperia Z2 and its successor, the Xperia Z3. Given the short amount of time between the release of the two phones, you'd be forgiven for just going for the latest version and being done with it.
But hold up just a second there. Although the Xperia Z3 is newer, it's also more expensive and many of the advances are just minimal. Design-wise, it looks pretty much identical to the Z2, even if it's a fraction of a hair thinner.
The display is still the same 5.2-inch triluminous 1080p screen as the Z2, with the only change being in brightness. The Z3 can hit 600 nits of brightness compared to the 460 on the Z2. Likewise, the rear-facing 20.7MP camera is still the same.
Sony has given the CPU a boost to 2.5GHz but kept the RAM the same at 3GB. In practical terms, in means the Z3 has a better battery life although performance, as I mentioned earlier, is similar.
There's no doubt that the Z3 is the better phone – as it already does everything the Z2 does. And, according to Amazon right now, there's only around £90 difference in price for a SIM-free handset.
With such a small gap it's probably worth going for the Z3 if you're buying off-contract today. The Xperia Z4 may be along any minute, but it will be significantly more expensive than both of its predecessors on release.
I would argue that the Z3 isn't enough of an upgrade to warrant the extra cash, especially considering there's probably an Xperia Z4 waiting in the wings for later in 2015.
- Read our: Sony Xperia Z3 review
John joined TechRadar over a decade ago as Staff Writer for Phones, and over the years has built up a vast knowledge of the tech industry. He's interviewed CEOs from some of the world's biggest tech firms, visited their HQs and has appeared on live TV and radio, including Sky News, BBC News, BBC World News, Al Jazeera, LBC and BBC Radio 4. Originally specializing in phones, tablets and wearables, John is now TechRadar's resident automotive expert, reviewing the latest and greatest EVs and PHEVs on the market. John also looks after the day-to-day running of the site.