Hands-on with the ASUS ZenFone 2

The ZenFone is back for a second run, bigger and better than ever

At its CES 2015 press conference, ASUS pulled the wraps off its latest Android powered smartphone, the ZenFone 2. The first ZenFone devices were announced in the very same building 12 months ago, and with the new one ASUS has come on a little with its main line of smartphones.

Design changes, beefier hardware, and some new software tricks all add up to a decent upgrade.

One of the most recognizable design changes is that the volume buttons have been moved to the rear. We liked it when LG did it and we like it again now ASUS is doing it. But, there's a catch. The power button hasn't been moved to the rear, instead being moved to the top. So it's maybe half as good as the implementation on something like the LG G3.

While moving the buttons has led to some incredibly thin edges – the curved back tapers down to a point – because it's a 5.5-inch phone it's not the easiest thing to press the power button without using your other hand. So it's good, but room for improvement for sure. But the curved back of the phone makes it really comfortable to hold, and while plastic it does boast a brushed texture.

On the hardware front, the range topper we're looking at here has, as mentioned, that 5.5-inch display at Full HD resolution. It's bright, vivid and sharp and all round pretty nice to look at. Underneath is Intel's latest 64-bit CPU and a stonking 4GB of RAM. ASUS is quite proudly boasting that they're the first Android smartphone with this much RAM underneath. First impressions of performance are good, and while pre-production trade show units aren't a great example of real world use, everything is smooth and there's no real sign of Mr Lag.

On the software side ASUS is now packing Android 5.0 Lollipop and the latest version of its Zen UI custom overlay. Visually it's a hybrid of Asus' own style and standard Lollipop, so we have the expanding notification tray and app switching window, but with a little Zen UI flavor in places. One of the big features of Zen UI is that all the custom apps are updated through the Google Play Store, meaning the latest and greatest versions arrive without the need for a firmware update.

ASUS is making a big deal out of the camera, too. While the ZenFone Zoom takes all the headlines in that regard with its optical zoom, the ZenFone 2 is no slouch, either. The 13MP camera makes some bold statements about "class leading" features such as low-light shooting and HDR, as well as a zero-lag shutter response. While the shutter response feels right on the money, we'll reserve judgment on the actual photo quality until we get one out in the wild.

The ZenFone 2 will cost from $199 when it goes on sale in March. A cheaper, lesser specced version with a 720p display is also going to be available, but the ZenFone 2 looks to be a reasonably well priced device all told. While information on retail and carrier support is currently unknown, it's definitely a decent sequel from ASUS.