Why? Well, that's easy: value. The OnePlus 3 matches the current flagship competition on the vast majority of specs and features, but manages to do so at about half the price. That's an incredible deal, and for the average phone buyer, saving a couple hundred quid is worth skipping out on high-end perks like a Quad HD display or modular add-ons.
If you're in the market for a new phone today, the OnePlus 3 might be the smartest option around. But what if you've just bought the OnePlus 2 within the past several months? The last-gen model has been quickly outmoded, but is the upgrade so significant that you can't possibly resist moving up to the OnePlus 3? Let's run through the comparisons.
YES! Look at that build
The most immediately striking thing you'll notice about the OnePlus 3 is that it looks like a proper, full-priced flagship phone now. It has the unibody aluminium build and an ultra-sleek design with some compelling curves, and while the design might be more familiar amongst the flagship pack than last year's model, we'd argue it's for the best.
Certainly, the OnePlus 2 stood apart from the competition in terms of looks, but it was also a larger and thicker phone than we expected from a top-end device. In other words, it looked like a mid-range phone that aspired to more, while the OnePlus 3 actually completes the trick.
Looks aren't everything, obviously, and we'd never tell you to drop a chunk of money purely for an aesthetic upgrade – but if the OnePlus 3 grabs your attention, it could be hard to resist.
NO! It's not a huge screen upgrade
Both the OnePlus 2 and OnePlus 3 have 5.5in 1080p displays, but they're not identical panels: the former used an LCD screen, while the OnePlus 3 makes the move to OLED. We all know the benefits of OLED displays, from deeper black levels to better energy savings.
That's true with the OnePlus 3's screen, and if we had a choice, we'd opt for OLED. However, given the same size and resolution, not to mention the fact that the OnePlus 3's display is a bit oversaturated compared to other top flagships, it's not enough of an overwhelming quality upgrade to nudge you onto a new phone.
MAYBE? Performance gets a boost
The OnePlus 3 matches many of the flagship headliners on the market today with its Snapdragon 820 system-on-a-chip, but then blows past other handsets by bundling in a whopping 6GB RAM. That's insane! Do you really need 6GB of RAM on a phone? We can't imagine so, but it's awfully reassuring to know you have it should you need it.
In day-to-day use, the OnePlus 3 is super speedy with its OxygenOS skin atop Android Marshmallow, and it handles glossy games and media with ease. But then again, the OnePlus 2 does much the same with its own apps and media, despite running a lower-end Snapdragon 810 and having "just" 4GB RAM included.
At this level, it's more processing power than the average user could possibly need for everyday usage. Might your phone experience be faster on the OnePlus 3? Totally. Is it enough to warrant ditching a perfectly good year-old phone? Doubtful.
YES! Sharper shooting within
You can find better back cameras on the market today than the OnePlus 3's 16-megapixel shooter, but it's one of the best in the ~£300 price range. We produced fine shots with consistency, and although it has a tendency to over-process photos at times, the results are still sharp. And the 8-megapixel selfie cam is no slouch, either.
Contrast that with some of the issues we've experienced with the OnePlus 2's 13-megapixel main camera, including the sluggish shutter and unsubtle HDR work. Again, it was a fine camera for the price last year, but the OnePlus 3's is much nicer today.
If you're constantly grabbing snapshots throughout the day, that could make enough of a difference to push you up to the OnePlus 3.
NO! Battery life is about the same
Looking for enough battery juice to get you through the day? In either case, you should be fine. The OnePlus 3 sees a dip in battery pack capacity, from 3,300mAh to 3,000mAh, but also has a more efficient processor. All told, both are strong all-day performers.
There is one big perk with the OnePlus 3: the included Dash charger, which boosts your charging speeds and lets you grab a 90% charge inside of 40 minutes. That's definitely a welcome addition, but we wouldn't scrap last year's phone just for faster charging.
VERDICT: Worth the upgrade?
Much as we love the OnePlus 3 and think it's the best new smartphone option right now, we struggle to recommend it as a necessary upgrade for OnePlus 2 owners. Its upgrades are meaningful, whether it's the performance boost, improved camera setup, or sleeker build, but they ultimately feel like small pieces of the larger puzzle.
And since much of the appeal of OnePlus phones is value, we doubt you're all that anxious to ditch a months-old phone to buy a new one, right? The OnePlus 2 is still a fine phone: one that we awarded five stars to last year and would still recommend at a discounted price. The OnePlus 3 is a nicer, better-rounded phone, but this upgrade doesn't seem essential.
On the other hand, the lower price points for both mean that if you choose to sell off your OnePlus 2 and put that money towards a OnePlus 3, you probably won't owe a whole lot extra to make the upgrade.
Still, if you're happy with the OnePlus 2, consider hunkering down for another year and seeing how OnePlus plans to top the OnePlus 3 next summer. We can't wait to find out.