The Retina Display vs 4K vs True Tone

What Is the Best Screen Resolution for a Tablet?

The new 12.9-inch iPad Pro has a True Tone display, but it isn't 4K. Apple

As the buzz over 4K television displays heats up, we are starting to hear more and more about 4k invading the world of tablets. But while companies like Samsung have slung around the 4K buzzword, these tablets have fallen short in the actual screen resolution category. And with Apple now touting their True Tone displays, we have another buzzword to contend with. Do we really need 4K tablets? And how does 4K stack up to the Retina Display? How about True Tone?

What is a Retina Display?

The confusing part about a Retina Display is that it comes with a lot of different screen resolutions. A 4K display is generally a 3,840x2,160 resolution regardless of the size of the display, but the resolution of a Retina Display usually changes based on the size of the display.

As termed by Apple, a Retina Display is a screen with a pixel density high enough that individual pixels can no longer be discerned by the human eye when the device is held at a normal viewing distance. The "normal viewing distance" is an important part of this equation because the closer you hold the device, the smaller the individual pixels would need to be before they become indistinguishable from one another. Apple considers the normal viewing distance of a smartphone to be around 10-12 inches and the normal viewing distance for a tablet to be around 15 inches.

The Retina Display distinction is important because any higher screen resolution doesn't provide any viewing benefit. Once the human eye can no longer distinguish individual pixels, the display is as clear as it can be. In fact, higher screen resolutions require more graphics power, which sucks more power from the battery. So exceeding a "Retina Display" can actually detract from the device.

Is 4k Just a Scam By the Television Industry?

There is an important difference between a tablet and a television. A television is used primarily to watch video. And to get the most out of the video we are watching, the resolution of our television set should match the resolution of the video. So even though televisions come in many different sizes, the industry needs a standard screen resolution to match the video produced with the resolution of the television.  It wouldn't do any good to have a higher resolution for a bigger television when the picture on the screen is going to be shown at a lower standardized resolution.

So, 4K is an important standard for the television industry. However, we use our tablets for much more than just streaming videos from Netflix and Amazon Prime. So in terms of a tablet, the "4K" designation has less meaning.  

Retina Display vs 4K

In terms of buying a tablet, the "4K" designation should only be a concern if your primary use is to use the device to watch television and stream video. The real number to look for is the pixels-per-inch (PPI) of the display.  PPI is determined based on the screen size and the screen resolution. Most tablets now display the PPI in the specifications.  

The 9.7-inch iPad Pro has a 9.7-inch display measured diagonally with a 2,048x1,536 resolution.  This gives it a PPI of 264, which Apple considers enough to be a Retina Display for a tablet. The 12.9-inch iPad Pro has a  resolution of 2,732x2,048, which also gives it a PPI of 264.   

In looking at a tablet, a PPI of around 250 or above is key to hitting that Retina Display range. Remember, anything more than a Retina Display simply causes the tablet to throw more wasted pixels at the screen, which sucks up more battery life. Interesting enough, the iPad Mini 4 has a PPI of 326 based on having the same screen resolution as an iPad Air 2 with a smaller 7.9-inch screen. No doubt, Apple thought keeping the resolution the same from a compatibility standpoint was more important than the extra drain on the battery, but the display itself would look about the same with a smaller resolution.  

A 4K resolution on a tablet should generally be considered only on tablets that measure 12 inches diagonally or more. This is why the first 4K tablets tend to be of this larger size. Smaller tablets with a 4K resolution are jumping on the bandwagon for a display that will eat up more battery power but not provide any clearer resolution than an iPad. Crazy enough, Sony actually produces a smartphone with a hyped 4K resolution.  

When 4K Isn't Really 4K

Samsung recently released the "4K" Galaxy Tab S3 tablet that sports a decidedly un-4K resolution of 2048x1536. This is the same resolution as the 9.7-inch iPad Pro. Samsung markets this Galaxy Tab S3 as a 4K tablet because it can accept 4K video even though it cannot actually output it onto its display.  This basically takes marketing buzz words into the bait-and-switch area. It also means you should be skeptical of any tablet referring to itself as 4K.

And What About True Tone?

Apple's newest displays for its iPad Pro line of tablets are now being labeled "True Tone" displays.  The True Tone display is capable of producing DCI-P3 Wide Color Gamut, which is a standard used by the music industry. The move towards "Ultra-High Definition" (UHD) in the TV industry is a move towards a wider color gamut as opposed to just increasing screen resolution ala 4K.

Another feature of Apple's True Tone display is the ability to detect ambient light and alter the shade of white shown on the screen to mimic the effect of light in the 'real world'. This is similar to how a sheet of paper might look more white under shade and more yellow directly under the sun.

Will 4K Eventually Go the Way of 3D?

While 3D TVs have proved to be a bit of a fad, 4K television sets are likely here to stay. However, it may take longer than some think for 4K to become the true standard. It take more space to store a 4K video, and more importantly, it takes more bandwidth to stream 4K. 

It currently takes around 5-6 Megabytes-per-second (Mbps) to stream 1080p high definition video. If you take into account the need to buffer and deal with they varying speeds of Wi-Fi, 8 Mbps would be more ideal. Currently, it takes around 12-15 Mbps to stream 4K video, with the idea connection being around 20 Mbps. 

For many people, that would eat up most of the bandwidth they get from their Internet provider. And even those with 50 Mbps connections would feel a major crunch if two people on their network tried to watch a 4K movie at the same time.  

And while we might be able to work around the issue, a company like Netflix or Hulu Plus would see a huge increase in the cost to stream video. And ISPs like Verizon FIOS and Time Warner Cable already struggle dealing with the amount of bandwidth Netflix alone takes up during prime time. The Internet itself might become unusable if there were widespread adoption of streaming 4K video.  

So we are not quite there yet. But from a pricing standpoint, 4K televisions are getting closer and closer to that consumer level. In a few years, most of us may think the extra $100 spent to upgrade to a 4K screen is quite worth it. It might actually take a little longer for Internet providers to be ready for it, but they'll get there.