Alongside its new flagship, the Nokia Lumia 930, Microsoft has launched two further Windows Phone 8.1 devices this year. The Lumia 630 is an affordable and likeable Windows Phone, but not a perfect one, while the even cheaper Lumia 530 went on sale earlier this month.

But as it rolls out new handsets, one of its older low-cost devices is continuing to sell well. The Lumia 520 was first announced almost a year and a half ago at Mobile World Congress 2013, but it's still on sale today, and it's even more affordable than the company's latest devices. As WPCentral reports, Amazon is now selling the Lumia 520 on AT&T for just $39.99 off-contract.

That low price is temporary, though - it is being offered under Amazon's 'Gold Box' promotion for today only, so don't waste any time if you're considering picking one up. The last time the 520's price dropped as low as this was eight months ago, shortly before Christmas.

The Lumia 520 features a dual-core 1GHz Qualcomm Snapdragon S4 processor and 512MB of RAM and 8GB of onboard storage, along with a microSD card slot. A 5MP rear camera is included, although there is no flash and no front-facing camera. Despite these limitations, the Lumia 520 scored very highly when we reviewed it last year, becoming one of our favorite smartphones ever.

Source: Amazon via WPCentral