Smartphone displays have rapidly improved at every single price point. Inexpensive smartphones often compromised on display quality, which ended up hurting much of the overall experience. However, even inexpensive smartphones now ship with IPS displays and high enough resolutions to render text without overwhelming aliasing.

The Lumia 640 has a 5" 1280x720 IPS display. At 294 pixels per inch, it’s fairly sharp for a phone of this price. It’s obviously not some 2560x1440 flagship phone, but I never felt like text appeared fuzzy or highly aliased. To evaluated the aspects of display quality beyond what you’ll see on a spec sheet we turn to our standard smartphone display tests. As always, measurements are performed with X-Rite's i1Pro 2 spectrophotometer and SpectraCal's CalMAN 5 software, with the exception of contrast measurements which are done with an i1Display Pro colorimeter.

Display - Max Brightness

Display - Black Levels

Display - Contrast Ratio

437 nits is a fairly good result for peak brightness. It’s not quite as high as the 500 and 600nit displays that you’ll see on flagship phones, but it’s noticeably higher than many other devices at this price point. The contrast is also pretty good. While the black level isn’t even close to the lowest we’ve seen, when you consider that many devices use CABC to cheat on contrast it’s actually a relatively good result.

Display - White Point

Display - Grayscale Accuracy

The greyscale results on the Lumia 640 are exceptional. RGB balance is great at every shade of grey, with only a very slight shift toward blue. All of the errors will only be visible if you compare static images with a reference monitor. There’s not much more to be said, as the greyscale accuracy on this display is essentially perfect.

Display - Saturation Accuracy

The next test examines saturations of primary and secondary colors on the display in increments of 20%. In this test the Lumia 640 does very well. There are definitely some issues with blue and magenta, and the fact that cyan maxes out at 80% saturation, but the overall accuracy is very good.

Display - GMB Accuracy

The final display benchmark is the Gretag MacBeth ColorChecker test. This test examines colors that are commonly found in the real world, and it’s the best benchmark of display color rendition. A display can hit its saturation targets accurately but fail to reproduce these color mixtures properly.

Fortunately, the Lumia 640 suffers from no such issues. Most of the colors are reproduced with a high degree of accuracy, with the big errors being in shades of blue. Skin tones are very well reproduced, which is something I’ve seen other devices struggling with in recent reviews.

Overall, the Lumia 640’s display is very good, and I would go as far as to say that it’s one of the best displays on a phone at this price point. It performs well in every category, from brightness, to contrast, to color accuracy, and the resolution is high enough to keep everything looking fairly sharp. I think Lumia 640 users will be very happy with the display on their phone.

System Performance Camera Architecture and UX


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  • lolstebbo - Tuesday, June 9, 2015 - link

    "Since this Lumia 640 is locked to Cricket Wireless, I'm unable to also test it on LTE, which is unfortunate."

    Why would the 640 being locked to Cricket prevent you from testing it on LTE?
  • Brandon Chester - Tuesday, June 9, 2015 - link

    Because I'm Canadian. Reply
  • milkod2001 - Tuesday, June 9, 2015 - link

    MS has less then 5% mobile market share...

    What will break this curse?

    1) another crappy low end phone? - NO

    2) high end Samsung / Apple like specs phone with better camera, mSD+rem. battery? - YES
    (MS needs to make killer phone people will talk about and think about getting )

    3) fixing missing apps -YES
    (MS as giant software company can not make the same in house apps as most popular Android / iOS apps? Or just pay developers to make the same apps for Windows Phone? How pathetic is that?)
  • colguy1 - Tuesday, June 9, 2015 - link

    Don't you think MS has not attempted to do that? Back in 2013 MS created a very beautiful Youtube app. I used it for a week in my Windows Phone. But Google made sure that it was removed from the windows phone store. Well known Windows Phone developer Rudy Huyn created an amazing client app for SnapChat. But when SnapChat removed all 3rd party apps, it removed this app too. This SnapChat app was miles better than the first party apps in iOS and Android. The developer requested many times to work with him to whitelist the app and get it in the Windows Phone store. But no response from the SnapChat. MS created a Pebble app and demoed it to the Pebble guy.. Little bit of google search will tell you what happened next.. It is not just entirely MS fault for the lack of apps. Reply
  • jakoh - Thursday, June 11, 2015 - link

    I can say to for no 3, the new cross compiling feature in windows 10 which will allow Java or Objective C to be compiled for Windows will help. Reply
  • Harry_Wild - Thursday, June 18, 2015 - link

    Microsoft needs to get out of the U.S. carrier exclusivity agreement with their high end models. Many people now go with unlock international models that live in the U.S. Total bizarre that Microsoft's home market; they screw the consumer in flavor of the carrier! Reply
  • mockyboy - Tuesday, June 9, 2015 - link

    I need a new non-contract phone and have been considering an Iphone. I have a Lumia 521 right now and even as a casual phone user it's gotten way too slow.

    The thing is whether the Iphone is worth the 5x higher price than the 640. I can get the 640 and an Ipad Mini for around 420 and still save $200. And I work from home, so honestly I'm really not a heavy phone user. The 640 seems like it would be fine for everyday needs, and the few apps I want I can get a Ipad Mini for.
  • StormyParis - Tuesday, June 9, 2015 - link

    Frankly, I'd get a Moto E or G instead. Here's Anand's Moto E conclusion: http://www.anandtech.com/show/9129/the-moto-e-2015... Reply
  • mockyboy - Tuesday, June 9, 2015 - link

    I hadn't considered those, thanks. Although for some reason I've been avoiding Android. I have no idea why. Maybe because I heard bad things about their low end phones, but based on that review I guess that's changed. Reply
  • Callum S - Tuesday, June 9, 2015 - link

    Either that or get a Lumia 640 and Surface 3 with accessories for about the same price as an iPhone by itself. I do however seem to be addicted to OneNote though :-)

    Understand completely in regards to not being a heavy phone user. It doesn't matter how powerful they get, for actually getting stuff done, there is no comparison to using either a mouse and keyboard or a stylus (for diagrams and notes). Until of course phones are at stage where they can be docked and or properly utilise other input methods like the notebooks and tablets can today.

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