iPad vs. Kindle: Which is the better e-Reader?

The iPad is indeed a useful, entertaining, engaging and disruptive product, but is it really a better e-Book reading device?
Written by Jason Perlow, Senior Contributing Writer


The iPad is indeed a useful, entertaining, engaging and disruptive product, but is it really a better reading device than the traditional e-Ink readers currently on the market? We put the iPad's backlit IPS LCD screen to the test and compared it to its competitors under various lighting conditions. (click here to view our testing gallery)

So after all of the fallout, just under three weeks after the iPad's availability on April 3, I've had a decent amount of time to spend with my new device and explore its capabilities. For the most part, the product has delivered very well on its promises as an industry leading and powerful digital convergence device, particularly in the consumption of Web, multimedia and informational content.

The iPad is a non-stop source for consuming updated news feeds, is a phenomenal casual web surfing device, is great for viewing and listening to streamed media, has freed me from my desktop for at least 3 or 4 hours during the work week and has allowed me to relax with technology over the weekend and evenings. In that respect, the device has already justified its purpose.

However, one of the reasons why I purchased the iPad was that I wanted a single device that indeed would be a universal content consumption device and would replace the e-Readers that I have been flirting with on and off over the last several years. I say flirting because I primarily use e-readers for recreational reading when I am on vacation or when I have ample time to spare.

Over the years I have been highly critical of e-Reader devices such as the Kindle. Their internal processing power has been limited and I have found overall performance and responsiveness to be slow, particularly as it comes down to user interface and screen refresh. Most importantly, their cost relative to their limited function, which is to read books has also been traditionally high when compared to multifunction devices.

eReader screen showdown: iPad IPS LED Backlit LCD versus e-Ink Displays (Gallery)

With the iPad now on the scene, and with other tablets soon to be available that will use LCD or OLED technology, has the e-Ink reader become obsolete? Or is this technology still relevant?

We decided to put the iPad against several e-Ink readers under different light conditions to determine which of the two technologies were more "readable". In other words, if you were handed one of each, which would you prefer to read with more? The answer, as we shortly found out, was not so cut and dry.

Click on the "Read the rest of this entry" link below for more.

Our Testing Criteria

In our tests we tried to simulate several common conditions when people would be reading e-Books:

Morning and Afternoon indoors in a living room using ambient natural lighting from a window source and off a patio setting.

Outdoors under direct sunlight or partial cloudy skies during weekends and vacation settings in clear weather

Evening, using Compact Fluorescent (CF) artificial light from a reading lamp in a study or bedroom environment

Evening, under dim lighting or complete darkness in a bedroom environment

I approached the tests from two perspectives: One, from my own personal use of the devices under these conditions, and the other from the perspective of a "Super Reader" with existing eBook technology experience.

A "Super Reader" is a person who reads on a voracious schedule in excess of a dozen books a month. I expected that I would get varying results between the Super Reader and myself, if not for the fact that our tolerances for the display units and our attention span will vary, not to mention our relative eye health.

The Super Reader I enlisted was our friend Sandi, who owns a Kindle 2 and reads approximately 20+ books per month. She's been an owner of the Kindle 2 for approximately five months and already has over 160 titles on her device.

Sandi, who is in her mid to late 40s, works from home and reads during various times during the day, so I considered her an excellent test subject. Both Sandra and I have to wear corrective lenses, I am age 40, nearsighted with a strong astigmatism (-6.50 and -6, left and right respectively) and Sandi wears trifocals.

The need for corrective lenses is not uncommon for bookworm types, and finding a heavy reader with near-perfect eyesight was not something I could easily do on quick notice (nor would it be a realistic representation of the average recreational reader) so I thought between her and myself, a casual reader and a heavy reader we'd have a reasonable representative sample.

The Devices

For our test devices we used an iPad Wi-Fi edition ($499) with standard Apple case, an Amazon Kindle 2 ($259.00) with a protective screen and scratch cover, and a SONY PRS-700BC, a slightly older generation e-reader.

In the case of the latter two devices, both are Vizplex e-Ink technology, with 16-level and 8-level gray-scale respectively. The iPad uses an In-Plane Switching LED back-lit Liquid Crystal Display (LCD) which is similar to display technologies used on current high-end notebook computers and Apple iMac screens.

On the iPad, and under all lighting conditions, we used both iBooks as well as Amazon Kindle for iPad and read similar material interchangeably on the reader units.

Daylight Reading Scenarios


The Perlow Living Room.

Both testing days occurred in Northern New Jersey on April 19 and 20th, 2010, where the skies alternated between partially cloudy and not cloudy with the southern part of the home having full and unobstructed exposure to very bright direct sunlight. As such, we used 90 percent closed black-out shades in the living room with open bay windows and closed skylights to control the amount of natural light entering the Living Room to acceptable reading levels for e-Ink and LCD display.

Using the PRS-700BC on April 19th I found I was easily able to read more than an hour of text content without experiencing significant eyestrain. With the iPad, I was only able to go for about 45 minutes using varied brightness settings on both iBooks and Kindle for iPad.

On April 20, Sandi fared slightly better on the living room couch,  citing about an hour of total tolerance to eyestrain on the iPad while adjusting various settings for text size and brightness level. Additionally, Sandra felt she would be able to read for at least 2 hours using her Kindle 2 under this lighting condition.

Both of us noticed that the Kindle application on iPad seemed to have a higher level of optimization for reading books under different ambient light conditions and would not exceed a certain level of brightness, whereas iBooks had full hardware control over the back-light and could push it all the way to the maximum luminosity.

In addition to the living room, we also both tried reading on the kitchen table immediately next to the glass sliding door facing the patio and my backyard, which introduced a larger amount of natural light.

Under these conditions I was able to read for approximately 15-20 minutes before experiencing significant eyestrain and discomfort. Sandi again fared a little better, with about 30 minutes of tolerance. In both cases we felt we could better handle the light conditions with our respective e-ink readers.

Outdoors, it was a total fail for the iPad. The screen immediately turned into a mirror on both April 19th and April 20th, and was completely unreadable no matter which application we used and at any brightness setting.

Both e-ink based readers had sharp text and were easily readable on the backyard table, which was beneath partially overcast skies on both dates. We did not bother to conduct readability tests with the iPad, and it was a given that this was an ideal e-ink scenario due to total lack of sun glare. Sandi indicated that she could read for several hours under these conditions without any eyestrain whatsoever.

On the 20th of April towards the late afternoon we were fortunate enough for the clouds to clear and experienced full and direct sunlight on my front lawn, so we positioned a chair there for Sandi to read for approximately a half an hour.

As with the previous test, Sandi indicated she would have no problem reading for several hours with her Kindle 2 under these conditions. Considering the poor results of the iPad with overcast skies from earlier in the day, we didn't feel it was necessary to conduct a readability test with that unit.

Night Reading Scenarios

While it became clear to us that e-Ink technology is vastly superior for just about every daytime reading activity using natural light, it came as a surprise to us that the iPad fared considerably better in artificial lighting and for dim light, full darkness and evening reading.


The Perlow Guest Bedroom.

For our night-time reading tests we used our guest bedroom on the night of the 19th from 10pm-12 midnight under complete darkness as well as with the assistance of a bedside Compact Fluorescent (CF) lamp.

For Sandra's visit on the 20th, we performed the tests in the late afternoon with the blackout shades completely closed and with the lamp off, which was her preferred evening reading condition as she occasionally reads in bed late in the evening with her spouse sleeping.

Reading with the bed lamp I found both the iPad and the e-Ink display to exhibit approximately the same level of eye strain, about 40 minutes of total reading time before I wanted to turn the lights out and read using the device's own illumination.

In total darkness, the weakness of the e-Ink displays become apparent because they rely on external illumination, so I used a Mighty Brite Xtraflex 2 LED ($15) with the SONY PRS-700 to provide clip-on lighting.

Using the Mighty Brite and the PRS-700 I felt I could easily read for several hours, but the LED light could very easily become distracting to my wife if I had to use it in my own bedroom, so this would only make sense in a travel/hotel scenario if I were by myself.

(NOTE: The PRS-700 has an integrated LED backlight, but I didn't use this to test reading for extended periods in low light or darkness because this model is no longer sold, and few e-Ink readers currently ship with integrated backlight.)

Sandi similarly felt that reading with her Kindle 2 in darkness with the Mighty Brite clip-on LED book light was comfortable and could read for extended periods with only a small amount of eye strain, but also indicated that this activity would definitely disturb her spouse, and does not read frequently during the late evenings in bed for this very reason.

On the night of the 19th, I initially felt that the iPad back-light was too bright and would almost certainly distract my spouse due to the large amount of white light emitting from the display.

I also felt that the iPad immediately produced too much eyestrain for use in total darkness in the standard Black on White text view no matter what brightness setting I had iBooks or the Kindle application set to, so I decided to experiment with White on Black text. This yielded some very interesting results.

Kindle for iPad in Black on White and inverse color modes in complete darkness.

I discovered that which e-Book reader application you use in total darkness seems to matter greatly, and that the Kindle application appears to be superior to iBooks for night time reading activities.

One, because White on Black text capability is integrated into the application using the Text/Font settings, and also because the Kindle application appears to make more effective use of screen estate and just plain looks better in the dark.

Two, it seems that iBooks is optimized for aesthetics and tries to reproduce a paper book reading experience, whereas Kindle's iPad book reader is fairly simple and straightforward and optimized for the simple act of reading electronic text. It should be noted that during our testing process we read standard novels only, and not illustrated books, so we cannot speak for color or illustrated book performance on the iPad.

To invert the text in iBooks, you need to go into the iPad's Settings applet and enable "White on Black" globally for the device under Accessibility. This inverts the color palette on the device across the board for all applications and you'll want to switch it back after you finish reading.

For my own personal use I find White on Black to be much more acceptable to me for use during the evening in dim light or dark rooms, and it also drastically reduces the amount of white light coming out of the iPad, so it is far less likely to disturb my spouse.

However, Sandi had the opposite reaction, feeling that the White on Black text caused an unacceptable amount of eyestrain. Instead, she was able to adjust the settings in iBooks using regular Black on White to approximately 10 to 15 percent brightness which produced strain-free illumination that she could read with comfortably for several hours.

The Verdict

The iPad appears to be adequate for light daytime indoor reading, but fails miserably as an outdoor reading device. Vizplex e-Ink readers such as the Kindle, the SONY line and the Barnes & Noble Nook still appear to be much more optimal for long duration reading indoors and outdoors during daytime hours.

However, both Sandi and I were very surprised how well the iPad performs in dimly lit rooms and in complete darkness. If it weren't for the considerable heft of the iPad, she would strongly consider using one to replace her Kindle for reading in bed at night, citing less chance for disruption of her spouse and less eyestrain than using a Mighty Brite or similar LED clip lamp with the Vizplex display on the Kindle.

We were both at somewhat of a toss up if White on Black or Black on White was the preferred color scheme for night time reading, but agreed that the Kindle reader application was superior to iBooks overall for serious readers in any light condition.

Have you had your own experiences with the Kindle and iPad under different light conditions? Talk Back and Let Me Know.

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