The Kindle Fire looked poised to disrupt the tablet market, with its low price point and easy access to Amazon’s products. Lately concerns have been raised about several features of the device. As Hayley Tsukayama reported :

The Kindle Fire is clearly designed for one thing: to make it easy for customers to buy Amazon’s goods.

But some are starting to question whether that convenience comes at the cost of security. In a Thursday column, technology reviewer Mark W. Smith identified the one-click feature on the Kindle Fire as a “big security problem.” The feature, which allows customers to store their credit cards with Amazon and avoid having to reenter their information each time, doesn’t have enough protections in place to avoid unauthorized purchases, Smith said.

It’s a problem similar to the one Apple faced when it came to light that parents around the country were facing high credit card bills after their kids made in-app purchases. Parents would authorize their credit cards once, and their kids would make micro-purchases that added up to big bills because Apple had a long window before it required repeat authorization. The company has since changed its policy to require a password for all in-app purchases.

The potential for bill shock is even worse on the Kindle Fire, because the Amazon shopping app isn’t limited to smaller purchases aimed at helping you get to the next level of a game. Since users can buy anything from Amazon through the shopping app, the costs could be much higher.

Users can reduce the risk of unauthorized one-click purchases by putting a passcode on their devices and locking the screen each time they set the device down.

Amazon has responded to several complaints about the Kindle Fire, and will push an update to its interface which will correct many of the issues first discovered after its launch. As Haykey Tsukayama explained:

The honeymoon period for the Kindle Fire appears to be drawing to a close as reports of customer complaints about the device’s Web browsing, touchscreen and other features have surfaced after the initial excitement about the tablet’s low, low price.

To address some of those concerns, Amazon is planning to push out an update to its Kindle Fire user interface in the next two weeks, the New York Times reported. The company has already updated the software for its tablet a couple of times, promising improvements to the tablet’s performance — and getting rid of root access to the device.

The new update will reportedly improve overall performance (again) and make some improvements to multitouch navigation, the report said. The update will also reportedly give customers a little more privacy by allowing them to edit their recent activity.

The report also hinted that Amazon will be rolling out a new device in the coming months, likely in the spring.

Despite some customer concerns over features of the Kindle Fire, Amazon says sales are continuing to rise. As reported:

Amazon’s Kindle lineup is en fuego and selling at a rate of more than one million units per week.

For three weeks in a row, the Kindle maker has seen this astounding statistic repeat itself.

The Kindle Fire is also the site’s top best seller, its most popular gift and the product that appears on the most wishlists for all of

“Kindle Fire is the most successful product we’ve ever launched -– it’s the bestselling product across all of Amazon for 11 straight weeks, we’ve already sold millions of units, and we’re building millions more to meet the high demand,”Dave Limp, Amazon’s Kindle-focused vice president, told Reuters today.

The VP further revealed that Kindle Fire sales had been growing week-over-week since Black Friday shopping began.

The Kindle Fire launched in late September. It represented a new breed in consumer mobile devices: a ereader-tablet hybrid that could contain books as well as surf the web, run apps, deliver and send email, display video content and more.

And at a price point under $200, it was destined to score big with holiday shoppers and any gadget-lover trying to deal with a tough economy.

By the beginning of this month, Amazon had already shipped between 3 and 4 million units, making the Kindle Fire the second-most popular tablet behind the iPad.

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How to update Kindle Fire software

Kindle Fire: Review roundup