Asus has already proven that just because something is affordable doesn't mean it needs to look and feel cheap. Think Nexus 7 and you'll have an idea what we mean. But at the Consumer Electronics Show 2014 in Las Vegas the Taiwanese company pushed a lot of effort into showing off its new line of smartphones. Or, as Asus calls them, Zenfone.

Available in three configurations, the Zenfone 4, Zenfone 5 and Zenfone 6 offer 4, 5 and 6-inch screens respectively. Ranging from the iPhone-size (and style) 4-inch model, to a 5-inch version, right through to phablet territory with the 6-inch top-spec offering.

Each model takes on a different feel in the hand, with the 4-inch being super-light, whereas the larger models have  a little more weight and, for our taste, feel the preferable options. They're also stronger on the specs front, although none is a truly high-end model.

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That's not to say they don't look spectacular for the money. The 5-inch model, for example, shown here finished in black, will cost just $200 (£122) but has the feel of a device far above that price. At 144g it's clearly a plastic build, but the way the screen joins to the rear section shows only a subtle seam - which in a black and white configuration looks rather suave.

Asus ships all the devices with Android 4.3 (with the promise of 4.4 on the way), but it made a big song and dance about its ZenUI user interface when Jony Shih, Asus CEO, took to the stage at CES. "Simplified icons and menus, a selection of themes ... and a clever What’s Next feature that helps users keep track of their lives," he said.

But the interface is hardly dissimilar from the familiar feel of Android. You've got all the usual icon arrangements, but peppered with some specific Asus apps - and it's only really within the likes of these apps that you'll get a sense of what Asus is looking to achieve.

All the models run really quickly to jump between applications and screens. We didn't test any heavyweight apps, and the results of those will differ depending on device - the Zenfone 4 has a 1.2Ghz Intel Atom processor, whereas the 5 and 6 models come with a 2Ghz variation. All have just 1GB of RAM. Not super-powered, but for the money we can't complain - and the point of these devices is to be affordable.

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Screen quality isn't the highest resolution available on the market. We spent most time with the Zenfone 5 and its 1280 x 720 pixel screen looked decent. It's less the resolution and more the brightness and viewing angles that work out well. The Zenfone 4 drops the resolution to 800 x 480 - but then given its $100 price point that's no surprise. And at the 4-inch scale it looks passable.

If you're after an affordable Android phone that doesn't look like a slab of cheaply pressed plastic then Asus could well be on to a winner with the Zenfone. And with black, white, red, blue and yellow colour options you can go a bit more personal with your choice too.