I have never tried to read outside with either the Apple iPad or the Amazon Kindle, so I have had to rely on the information I was able to discover with Google.

There appears to be quite a lot of controversy over which is the best tablet to read with outside. I suppose it would depend on whether you were trying to read in sunlight as to how easy this would be, I am an avid book reader and I would not try to read in full sunshine with a book, so I wouldn't try it with a tablet either, it's just not pleasant or practical.

These are some quotes from sites that I found, I have put the links below so that you can read the full articles.

This is from whatisnew.com;

"Can you read the Apple iPad display while outdoors? Do you need to be in the shade or can you see it in full sun? What if you are in the bright desert?

I live in in the mountains in Prescott, Arizona, but today I’m in Scottsdale visiting family. We’re taking the opportunity to play with the Apple iPad outside in the bright sunshine so we can answer these viewing questions. Here are photos & videos from this exploration.

Overall, reading the iPad outside is acceptable because of the application design. When you’re able to adjust application font size to make larger than average and can increase screen brightness all the way, then it’s readable."

thenextweb.com says;

"Oh dear, this is just fanning the fanboy flames. Amazon has produced a commercial that is sure to excite and ignite partisans of both Apple and Amazon.

The ad spot focuses on how difficult it is to read your iPad outside, and how easy it is to use a Kindle in the same situation. The screen differences (backlight versus e-ink) explain the experience differential, but that is not the point; Amazon wants to make the iPad look overpriced and just plain impractical, the technological reasons behind are of less significance."

I have attached the advert on the video link below.

and from unplggd.com;

"We read and photographed the devices in the following lighting conditions: bright sunlight outdoors, partial shade outdoors, shaded outdoors, and indoors indirect light. Both devices were left to the default font and brightness settings.

After several days of iPad and a year of Kindle usage, we arrived at the following conclusions.

In conclusion, it looks like our Kindle is not going to be usurped as our e-reader of choice by our iPad. While we love that the iPad is more than an e-reader, we do not like how difficult it is to read outside, the incredible amount of glare (even indoors, all too often all we could see was our reflection instead of the text), and the weight (one handed reading on the train is a serious no-go). Reading on the iPad also does not provide the same book-like experience as it does on the Kindle. Thanks to the e-Ink display on the Kindle we really are able to forget that we are reading on an electronic device. The e-Ink display is also much easier on the eyes and does not give us the same eyestrain that extended reading from the iPad or laptop does."

I guess a lot is down to personal preference, these articles are worth reading in their entirety, I hope this helps.