Amazon's new $90 Kindle is really good and includes a backlight for the first time

Amazon recently upgraded its entry-level Kindle with a couple of new features, including a backlight for the first time in this price range. It's available on Wednesday, but I've been testing it for the past few days and have a few thoughts before you buy one.

I'm a die-hard Kindle fan, and this is a very good model. It's the best Amazon has ever introduced at a sub-$100 price. It only costs $90 compared with the mid-range $130 Kindle Paperwhite. But there are a few reasons why bookworms may want to spend that extra $40 for Amazon's more feature-rich Paperwhite.

Here's what you need to know about the new Kindle before you order one.

The biggest change to the latest Kindle is the new backlight. Previously, if you wanted to read at night with the most basic Kindle, you had to leave the lights on. Now, Amazon is bringing a feature that has been available only on its more expensive devices down to the most basic. I love the backlight option, since it lets me read at night next to my wife without keeping her awake. It's a must-have for any Kindle I buy.

There are four backlights on the Kindle, which theoretically should mean that the lighting isn't as even as it is on the Paperwhite, which has 5 LED backlights. But I found the difference was hardly noticeable. It has the same 6-inch screen as the Paperwhite, but the body is slightly smaller, which I liked. You can carry it in a big pants pocket if you need to, or toss it in your bag where it won't take up much space.

I spent much of the last weekend making my way through a couple of books. I finished "Eleanor Oliphant is Completely Fine" and read more into "Pachinko." I have good eyesight, and I could definitely tell that the 167 pixels-per-inch resolution of the new Kindle wasn't as sharp or easy to read as the 300 pixels per inch on the Kindle Paperwhite. Text just looks slightly blurrier, especially in smaller menu items.

This isn't a huge deal. I was still able to read a book just fine, and I wouldn't have known any better had I not been coming from the regular Paperwhite I own. If you're coming from books and have never owned a Kindle, this won't bother you much.

There are a couple of other features, like the option to play back Audible Audiobooks through Bluetooth headphones. It's a good option to have if you prefer audio books, but you can just as easily listen to them from the Kindle app on your phone, which probably has more storage.

Battery life is really good. After reading for several hours over the weekend and through Monday, I still had more than 70 percent of the battery life left, even with the backlight switched on. Amazon promises up to four weeks of battery life, and I typically get close to that with most Kindles.

There are a couple of things I wish Amazon changed. It still uses an old microUSB charger, one of the few I know of that still do. Most new gadgets have adopted the newer USB-C standard, which can help charge devices faster. Plus, I'm more likely to have a USB-C cord in my travel bag than a microUSB cable, even though the Kindle ships with one. It's just a little less convenient.

The 4 GB of storage is plenty for me, since it still can hold thousands of books. But you'll want more storage if you're planning to use the Audible audiobook feature. You can't upgrade the storage, so the next best option is to consider the Kindle Paperwhite, which starts with 8 GB of storage.

Also, the new Kindle it isn't water resistant like the Kindle Paperwhite or $249 Kindle Oasis. Consider another model if you're planning to read on an inner-tube in the pool or at the beach.

It doesn't come with a case either. As a long-time Kindle owner I've found the screens can be prone to scratching if you leave them in a bag. I recommend buying the $30 fabric cover, which Amazon sells.

Finally, the interface felt slow to me at times, particularly when I was trying to back out of a book or move through the Kindle Store to find new books. It's not a deal breaker, but it just didn't feel as fluid as the experience on Amazon's more expensive Kindles.

I think most people shopping for a new Kindle should buy the Kindle Paperwhite, mainly because the text is much sharper and you get twice the storage.

But if you're coming from an old Kindle and you loved it and just want a backlight, then the new Kindle is a good buy. And if you've never had an e-reader before and don't want to spend a lot of money before you know how often you'll use one, then consider the new Kindle to get your started.

You get a lot for $90 without breaking the bank.

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