Review updated September 17, 2015

As a background, I am a retired Information Systems professional and I am writing this review from the perspective of being a long-time Kindle user. I have all the current e-readers and Fire devices from Amazon including the basic Kindle, the 2013, 2014 and new 2015 Paperwhite, the Fire HD6, Fire HD7, Fire HDX7 and Fire HDX8.9. This review is for the 2015 “All-New Kindle Paperwhite.” The attached picture shows the 2014 Kindle on the left and the new 2015 Kindle on the right. Here is the summary of my initial impressions of the 2015 model versus the 2014 model.

I am somewhat disappointed in the 2015 version as there is not a huge improvement over last year’s model. The Paperwhite made many improvements from its original first generation 2012 model to its second generation 2013 model, especially in the display and processor area. The 2013 model came with 2 GB storage, a wonderful display, a great battery and was the e-book “workhorse.” The second generation 2014 model changed by only increasing storage to 4 GB. The third generation 2015 model increased the display resolution but reduced the battery life slightly.

WHAT COMES IN THE BOX: A Paperwhite device, a quick-start guide and a short USB cord. Amazon still does not supply a power adapter.

SIZE: It’s the same identical size as the older Paperwhites. The weight has been reduced slightly from 7.3 to 7.2 ounces, a fraction of an ounce, most likely because of a smaller battery.
The good news is that all cases that fit the other Paperwhites will fit the 2015 version!!

DISPLAY: The resolution has been bumped up to 300 ppi, equivalent to the Voyage. However, in practical use, I can’t tell the difference unless I put an earlier version next to the new version for comparison. Unfortunately, when I place them side-by-side, I noticed that the new Paperwhite is not quite as bright as the older models when set at the same brightness level. This is more noticeable at lower settings. Also, my Kindle has a slight shadow area along the bottom that appears as a small gray smudge and isn’t quite as evenly lit as the rest of the display. It is very small but noticeable. The logo on the bottom of the screen is now shiny black against matte black on the plastic case instead of being displayed in silver lettering. It's difficult to see except when viewing the shiny "Kindle" reflection at an angle to light.
(September 2015 update: The Kindle logo is how I tell my new 2015 Paperwhite and older Paperwhites apart. They are that similar!)

BATTERY: The battery of the 2013 and 2014 Paperwhites are rated a third larger than the new model. And it is noticeable! When operating simultaneously, the new PW battery drains much faster. It is currently rated at 6 weeks of ½ hour average daily usage versus 8 weeks for the older models. That specification translates to 21 hours of use versus 28 hours of use for the older models.

(September 2015 update: I was on a week-long vacation trip but forgot my chargers. I had the 2014 Kindle with me, and as I was on vacation, I read a lot. The battery lasted--barely--the entire vacation. Given the shorter battery life, the 2015 model would have lost power before I came home. Normally, this shouldn't be an issue for most people as the 2015 battery does last a long time. But.... I am so spoilt by not having to carry a charger on trips, even long trips.)

STORAGE: Nothing has changed. It comes with the same 4 GB of storage. Mine netted 2990 MB free space from the factory. This number will vary slightly from device to device depending on the actual hard drive.

HARDWARE: Alas, there is still no audio with the Paperwhite. So you still can’t play songs in the background or listen to Audible books. If you need audio features, you may want to look at the Kindle Fire lineup as audio capabilities are not available on the PaperWhite, standard Kindle, or the Kindle Voyage. (September 2015 update: I still wish I could listen to Audible books like you could on the Kindle Keyboard.)

Wifi: Nothing has changed. I had hoped for an upgrade to 802.11ac or at least add the less crowded 5-Ghz range of wifi. If you are in a wifi crowded area, you will need to be closer to your router to download books. While the Paperwhite does not use a lot of bandwidth, it does need to be able to communicate with a router for WhisperSync to work and to download books.

It is possible that the new Kindle Paperwhite either has a slightly faster processor, or more likely, the memory has been upgraded from 512MB to 1024MB to match the Voyage. I have over a thousand books installed. To keep track of what I have, all books are added to collections, such as “Reading Queue” for those I have not read but want to read, and “Already Read” for those books I have already read. In addition, my books are also categorized by genre collections such as “Crime/Mystery/Thriller,” “SciFi/Fantasy,” "Historical Fiction," "Romance," etc. Categorizing my books helps me considerably when I wish to find a new book to read in my library which I have not read and what I want is a Mystery novel, but not a SciFi. When I download a new book and try to add it to the appropriate collections for later enjoyment, the process can be extremely slow, so slow that sometimes, I am not sure that I have even touched the check box in the add-to-collection screen because it takes forever to respond. The 2015 Kindle seems to be faster in that area.

(September 2015 update: I've noticed that the speed is directly related to the strength and quality of the WiFi signal. I am in a crowded WiFi area and although I can get a fairly good signal, the speed definitely degrades when I am not in the same room as the router. I still wish it had a 5Ghz antennae as that bandwidth is less crowded and faster.)

SOFTWARE: The user interface on the new Paperwhite is identical to the old Paperwhite except that the new Paperwhite comes with the Bookerly font installed. Those who own one of the new Fire tablets already have the Bookerly font for comparison. Personally, on the Paperwhite, I like the Caecilian and Palatino fonts as much as I do the Bookerly. It seems that the best font for reading changes depending on the book and the magnification of the font. (There are still eight size magnifications.) However, the firmware version installed with my 2015 Paperwhite was a version behind. The Firmware Version installed on the 2015 model is Kindle 5.6.1.1 (2634130033) versus Kindle 5.6.2.1 (263439002) installed on my 2014 model.

(September 2015 update: Amazon has updated the software on all their Kindles so the Bookerly font is available on all the devices.)

WITH SPECIAL OFFERS OR WITHOUT?? If you buy a case that automatically shuts the device off when closed and turns on when opened, I strongly recommend paying the extra $20 for removing the ads. If you have special offers, the Kindle still needs to be swiped from the lock screen to get to the page of the book where you left off. If you do NOT have special offers, when you open your case, you are immediately brought to the book and page where you stopped reading. No lock screen! Having a Kindle Paperwhite without special offers is wonderful. Open up the case, Kindle turns on and you pick up right where you left off. Close the case and it turns off. No extra finger swipes! This is true only for the Kindle e-readers. The Fire tablets continue to open up to the lock screen which must be swiped irrelevant of whether you have special offers or not.
NOTE: I received the advanced order of the 2015 Paperwhite on June 30. I was not able to order the device without special offers. Normally, you should be able to pay the upgrade difference online to remove special offers. Unfortunately, the device that I have received does not have an option to remove special offers for this device only! I do not know if this option will be available for all new orders or if they will correct the oversight in the future. So, order the device without special offers if you think you will ultimately want that because it is possible that you will not be able to remove them in the future.

(September 2015 update: Amazon fixed the option to remove special offers. And I still recommend that you buy it without special offers if you use a case that automatically turns it on and off.)

SUMMARY FOR THOSE LOOKING TO UPGRADE:
This is what has changed from the 2014 model.
PLUS: Higher resolution screen with Bookerly font. Possibly quicker when managing large numbers of books. (September 2015 update: Bookerly font is now available on all Kindle devices including older Paperwhites)
MINUS: A smaller battery and shorter time life between charges. No power adapter.
NEUTRAL: The "kindle" logo at the bottom of the 2015 model is now black on black instead of the silver color at the bottom front of the 2014 model.
(September 2015 update: The Kindle logo is how I tell my newer and older Paperwhites apart.)

THE VERDICT: The new Paperwhite is still the state-of-the-art e-ink e-book reader. The only things I can think of to improve the Paperwhite is to add a power adapter, a longer USB cord, bring back the longer battery life of the earlier model and perhaps make it waterproof.

(September 2015 update: the Paperwhite is still my favorite reader. I also like the Voyage but not enough to justify the huge price difference.)

Although the Paperwhite is only an e-reader and not a tablet, there are other considerations:
* No distraction from email
* No distractions from text messages
* No distractions from phone calls.

SHOULD YOU BUY? If you own last year's Paperwhite - I don't think it is worth the upgrade. If you do not own an e-reader or have a 2012 or earlier Kindle version, definitely get the Paperwhite. It has the best mix of features for the price compared to the other Kindle e-reader models. If you are considering upgrading from the current basic $79 Kindle, definitely get the Paperwhite. If you are considering whether to get the Voyage or the Paperwhite, ask yourself, "Is getting the Page Press area at the edge of the screen worth an additional $80?" If not, get the Paperwhite.

(September 2015 update: I really like both the Paperwhite and the Voyage. But I can't tell you which one to buy. If you are the type that will buy a Cadillac instead of a Chevy, buy the Voyage. It is definitely a very nice reader. Personally, I like the Paperwhite. Even though the Voyage is slightly smaller and lighter in the hand, there is something about the Paperwhite that makes me grab it instead.)

For reading, I prefer the Paperwhite over all the readers including the Fire tablets, the basic Kindle and even the Voyage. It’s optimized for readers and reasonably priced. You can throw it in your purse or pocket for traveling, even for reading in the doctor’s office waiting room. If you forget to charge it overnight, it will still have enough juice to get you through the next day or two. You can read it on the beach in BRIGHT, BRIGHT sunlight or at night under DARK, DARK moonlight. Whether you sit on the front porch or hide under the bed covers, you can enjoy reading books with the Paperwhite. In addition, there is a huge selection of case styles and colors to trick out your Kindle to match your personality and reading style.

If you want to save a little money, Amazon is currently selling the 2014 model for $109. Although it doesn’t have the Bookerly font, it does have a better battery. You can’t go wrong with the 2014 model either, especially when it is slightly cheaper.

(September 2015 update: My older Paperwhites have been updated with new software and now all have the Bookerly font. Unfortunately, the 2014 model is no longer available for sale through Amazon.)

FOR NEWBIES: You might want to explore the following features.

VOCABULARY BUILDER: The Amazon Kindles have a tool called Vocabulary Builder which is not available in the Fire tablets. Vocabulary Builder is supposed to help you learn new words while you read: words you look up in the Kindle's dictionary are stored in Vocabulary Builder. You can review those words, test yourself with flash cards, even see where in a book you highlighted the word and remove the word from your list when you’ve mastered it.

PAGE FLIP: When you're on a page, swipe up from the bottom, and a slightly smaller pop-up of the page appears. The pop-up has page turn arrows to go back or go forward in the book (you can also just swipe the pop-up page). When you're ready to return to your original page, press the "X" in the upper right corner of the pop-up, and the pop-up page goes away.

HIGHLIGHT: The highlight feature allows you to highlight (in black-and-white of course) a particular passage in a book and save it so you can go back to it at a later time. You also have the option of turning on an option that shows you other popular highlights from other readers of the book. This is a VERY useful feature, especially for non-fiction books as 99% of the time, the highlights other users have made point out very important sentences and paragraphs in the book. Note that this feature does not show EVERY reader's highlights, it only shows the most popular ones and even tells you how many readers have highlighted a particular section. This can be turned on or off if you find it distracting.

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