Following the recent release of Windows 10 for PCs, now is a great time to take another look at smartphones running the mobile version of Microsoft’s iconic operating system.

And if you’re looking for a reasonably priced mid-range handset with several features that are more at home on a pricey flagship device, there’s no better choice than the Lumia 640.

I recently spent a few weeks with this unassuming but full-of-surprises smartphone and handed it back impressed and wishing I could have had it for a bit longer.

Those familiar with the Nokia Lumia range will instantly recognise the 640’s lineage despite the Microsoft branding on the back – the Redmond, Washington-based multinational finalised its purchase of Nokia’s mobile division last year.

If the trademark plastic body – Microsoft prefers the term polycarbonate – and rounded corners weren’t enough to tip you off, one look at the crisp, bright 5-inch display replete with Windows’ distinctive live tiles will do the trick. For the past few years Lumia handsets – with a few niche exceptions that never went anywhere – have been the only devices to run Windows mobile.

At present, the 640 still runs Windows Phone 8.1. But Microsoft has promised it will get the update to version 10 as soon as it’s available for public release. At the moment it is being torture-tested for bugs and other flaws by thousands of Windows Insider volunteer beta testers.

Microsoft hasn’t announced a release date for Windows 10 for hand-held devices, but there are rumours that it could be sometime in September.

In the meantime, you’ll have no complaints about Windows 8.1 on the Lumia 640. I found it snappy and responsive without any of the lag and jitters you sometimes experience even on premium smartphones running competing operating systems.

For those who judge a device on its spec sheet alone, this performance may come as a surprise given that the 640 is equipped with a rather underwhelming sounding 1.2GHz Qualcomm Snapdragon 400 processor with just 1GB of RAM. But not if you know Windows 8.1 – and its successor Windows 10 – have been carefully optimised to have low system requirements so they will work almost as well on entry-level devices as they do on high-end smartphones.

What did surprise me was the camera. I wasn’t expecting much, given the price, but I managed to capture some pretty impressive images in a range of lighting conditions with the 8-megapixel rear-facing snapper. Sure, it’s not in the same league as imaging powerhouses like the iPhone 6 and Samsung Galaxy S6 – especially the front facing 1-megapixel “selfie” camera – but there’s not much to touch it in the mid-range market.

The build quality is great and the Lumia 640 feels solid, if a little slippery in hand thanks to the smooth finish on the black plastic back. I’d have preferred a more brightly coloured matt back, but that’s something that should be easy to rectify as it’s removable – and presumably replaceable with a choice of after-market backs in a range of colours.

Taking off the back reveals another neat feature of the 640 model I reviewed – two SIM card slots. I popped my usual SIM into one and a data SIM from a competing network into the other and found the freedom to switch between the two based on coverage and the best price at certain times of the day liberating.

It’s pleasing to see that the cellular operators are finally starting to stock more and more dual SIM phones after giving them the cold shoulder for years.

The 2500 mAh battery is removable, another plus, so you can swap it out with a spare if needed, although I found it easily lasted a working day and well into the evening, even with heavy use.

Less impressive was the miserly 8GB of internal storage. This is redeemed somewhat by the fact you can beef this up by as much as 128MB with the addition of an after-market micro SD card.

For those still on the fence, Microsoft is sweetening the deal by offering a free one-year subscription to Office 365 Personal, valued at R750, which includes free 1TB of OneDrive storage.

If you’re already embedded in the Microsoft ecosystem with a Windows desktop or laptop and happen to be in the market for a mid-range smartphone selling at a a near entry-level price, the Lumia 640, which starts at around R2 500 on prepaid and R170 a month on contract, is a no brainer. Heck, at that price it deserves a serious look whatever phone or computer you’re currently running.


Follow Alan Cooper on Twitter @alanqcooper