Superfast 4G LTE has long been a luxury feature only found on top-end phones with lofty price tags. It's steadily become more affordable over the past couple of years and is now beginning to be found at the budget end of the market as well.

The HTC Desire 510 is just such a phone. This 4.7-inch Android KitKat device doesn't have the most impressive specs around -- an 854x480-pixel display and 1.3GHz quad-core processor certainly won't spark much excitement among the tech elite -- but at only £90 on pay as you go with O2 in the UK, it's an extremely affordable entrance into the world of 4G LTE.

In the US, you can pick up the Desire 510 from BestBuy on the Sprint network for $1 up-front on a $9 per month contract. Australians can nab the phone for AU$179 on pre-pay from Telstra.

Design

If you've been eagerly eyeing the sleek metal curves of the HTC One M8 , but don't fancy its massive price tag, the Desire 501 won't be the affordable replacement you've been hoping for. It's a chunky beast, measuring 10mm thick and weighing a fairly hefty 158g.

Although the front has a speaker grille above the display -- reminiscent of the "BoomSound" speakers on much of HTC's pricier range -- it's generally a very uninspiring design. The back panel's matte plastic cover provides nothing of any interest, particularly in the black colour scheme I saw. The white version you can see on HTC's website looks a little prettier.

Andrew Hoyle/CNET

Still, it's difficult to demand too much effort in elaborate, fancy designs for such a cheap price. It's certainly functional and its chunky size makes it easy to grip. It definitely feels like it can take a few knocks and bumps without shattering into smithereens.

The speaker isn't as loud as the two powerful ones on the One M8, but it's louder than you'll find on many phones, and its forward-firing position means the sound isn't muffled when you lay it flat.

The top edge is home to the power button -- a more awkward location than on the side, in my experience -- while the volume buttons are on the left edge. The back cover is removable, providing access to the SIM-card slot, the removable battery and the microSD card slot. You'll probably want to get a microSD card too, as the 8GB of built-in storage won't last long once you start downloading apps and games.

Display

The 4.7-inch display has a resolution of 840x480 pixels, which is the absolute minimum I'd expect to see on any smartphone, even at the budget end of the market. Less than HD, it results in a pixel density of 208 pixels per inch -- way below what you'll find on the One M8, the One Mini 2 or the Desire Eye .

Andrew Hoyle/CNET

Of course, those phones cost way more than the 510, so I can't in all good conscience expect the same quality display on such a cheap phone. The UK-only EE Kestrel is £10 more expensive, but has a slightly higher 960x540-pixel resolution. The 510's screen is adequate for the absolute basics. Text is sharp enough to read easily enough, but it has a definite fuzziness to it that you won't see on higher definition panels.

It's fairly bright at least, managing to counter much of the reflections from our office overhead lights. Colours are a little cold, but I've certainly seen worse. If you only really want a smartphone for texting, Twitter and a spot of light gaming every now and then, the screen will be fine.

Android software

The 501 runs Android 4.4.2 KitKat, which is a couple of versions old now, but forgivable, given the cut-down price. HTC has applied its Sense software over the top, so the interface looks identical to the one you'll find on the top-end One M8.