Specs at a glance: Microsoft Lumia 950 Screen 2560×1440 5.2" (564ppi) AMOLED OS Windows 10 Mobile 10586 CPU Six-core Qualcomm Snapdragon 808 (two 1.8 GHz Cortex-A57 cores and four 1.4 GHz Cortex-A53 cores) RAM 3GB GPU Adreno 418 Storage 32GB, microSD Networking Dual Band 802.11a/b/g/n/ac, Bluetooth 4.1, GPS, GLONASS, BeiDou Bands GSM/EDGE: 850/900/1800/1900MHz

UMTS/WCDMA: Bands 1/2/4/5/8

LTE (FDD): Bands 1/2/3/4/5/7/8/12/17/20/28

LTE (TDD): Bands 38/40/41 Ports USB 3.1 Type-C, 3.5mm headphone jack Camera Rear: 20MP f/1.9, 26mm, 1/2.4" sensor, OIS, 3-LED flash, 4K30/1080p60 video

Front: 5MP f/2.4, 1080p video Size 145.0×73.6×8.2mm Weight 150g Battery 3000 mAh Starting price $598.99 / £420 Other perks NFC, fast charging

The wait for a flagship Windows Phone has been a long and rather unhappy one. Many mobile operators try to encourage people to get new phones each year (which strikes me as astonishingly wasteful), but for most of us two years between phones is about right. That much wear and tear is enough to make most phones look a little tatty, and two years of technological progress normally yields upgrades that we can actually feel.

The first generation of Windows Phone 8 devices, however, was released three years ago in November 2012. Initially, the AT&T-exclusive Lumia 920 was the flagship Windows Phone 8 device, and its siblings for other networks came a little later. The Lumia 925, on T-Mobile, was released in June 2013, and the Lumia 928 for Verizon came in May 2013. Anyone who bought a member of that 92x generation is long overdue an upgrade.

Problem is, there hasn't been a Windows Phone for them to upgrade to. The most direct successor to the Lumia 92x generation was the Lumia 930, released in February 2014. But its American version, the Icon, was Verizon exclusive and therefore useless to most. On top of that exclusivity, the phone was poorly supported by Verizon with extremely slow firmware updates. It fundamentally came at the wrong time to boot: too soon for owners of year-old Lumia 928s.

There should have been a new generation of Windows Phones in late 2014—or, at a pinch, early 2015—to support this de facto two year cycle. But while such a phone was planned, it was cancelled for reasons that have never really been made public, leaving an unsatisfactory gap. This gap meant that people willing to give Microsoft's minority platform a go were left in the lurch, and the platform as a whole lacked any kind of aspirational model to demonstrate its value and show its worth.

Fast forward, Microsoft finally announced a pair of flagships last month: the Lumia 950 and 950XL. The two are close siblings. They differ in screen size (5.2 inches or 5.7 inches), processor (6-core Snapdragon 808 and 8-core Snapdragon 810), and battery capacity (3000mAh and 3300mAh). Otherwise these phones are equivalent: 2560×1440 AMOLED screen, 3GB RAM, 32GB storage, USB Type C with rapid charging, Qi wireless charging, 20MP rear and 5MP front cameras, and biometric iris unlocking.

Both also usher in a new operating system: Windows 10 Mobile. Microsoft has spent years trying to converge its platforms, and with Windows 10 Mobile, it has finally done it. Universal Windows Apps, running on the Universal Windows Platform, can credibly claim to allow the same application to run on and target the phone, tablet, and desktop with touch, mouse-and-keyboard, or both. But it's the hardware that we will focus on today, specifically the Lumia 950's hardware. It officially launches on AT&T today while the Lumia 950 XL should land in a few weeks. (A full review of Windows 10 Mobile will come at a later date.)

(Some) benchmarks

That new Windows Phone flagships are so overdue has been nothing but bad news for the platform. Even people who otherwise like the platform, develop for the platform, evangelize for the platform have jumped ship for lack of hardware. And for those that stayed, the delay has also placed tremendous weight of expectation on the new flagships.

Unfortunately, the Lumia 950 does not really live up to those expectations.

As best I can tell, the Lumia 950 is a perfectly adequate phone. But there are limitations to my testing, and I only received the handset late on Monday. Although Microsoft intends to sell unlocked devices that will work with both T-Mobile and AT&T, currently only AT&T-locked devices are available (including review units). My handset was supplied with an AT&T SIM, but there has been some issue with activating it, and the carrier lock means that my personal T-Mobile SIM won't work. As such I have no idea how the Lumia 950 fares as an actual telephone.

I was also unable to run our usual browser-based battery test, because the screen times out after a maximum of five minutes, and there's no obvious way to prevent this. This isn't an issue when watching videos on the phone, as the screen remains on, but it is a problem for our browser-based non-video workloads. Such is life.

Adequate? I mean, the specs are perfectly decent. High end, even. The 950/950XL pair in a lot of ways mirror the Nexus 5X and 6P Android flagships. There's the same screen size split (5.2 and 5.7 inch) and same processor split (808 and 810), though Google adds a RAM differentiation (the smaller phone only gets 2GB) and screen resolution change too (the 5X is only 1920×1080. Only! As if 423 pixels per inch were somehow inadequate). The claim to be flagships is perfectly credible, at least based on the internals.

The ridiculously high resolution screen on the Lumia 950 is glorious too. I'm a total sucker for AMOLED. While the color accuracy may have some flaws (I don't know, I'm not a colorimeter), the rich, vibrant colors and the jet black blacks win me over every time. There's a palpable crispness that the resolution makes for beautiful text and crystal clear pictures. I love it.

Performance, on the other hand, is something of a mixed bag. Windows Phone has a reputation for being surprisingly smooth and quick even on low-end hardware. Windows 10 Mobile seems to retain that strength. Browser performance varies but feels broadly acceptable.

But 3D performance in Gfxbench seems really slow. The hardware in the Lumia 950 is functionally identical to that of the Nexus 5X, and so its 3D performance should be more or less identical. The phones obviously have different driver stacks; Gfxbench uses Direct3D on the Lumia 950 and OpenGL on the Nexus 5X, but that shouldn't really cause much in the way of performance differences. It's possible that the fault lies with Gfxbench somehow, but I'd guess that the Direct3D drivers simply aren't very good.











This is the kind of thing that would probably matter more if there were an abundance of games for the platform; something that might equally provide the impetus to make the drivers better. As it is, I don't know if it's ever a problem. There wasn't anything I did on the phone that showed off this weak 3D performance, but these metrics are certainly not what I'd hope to see.

Listing image by Peter Bright