The new price for the devices is $269 for the 16-gigabyte Wi-Fi version, down $30, and $399 for the lowest-price 4G , LTE high-speed data Kindle, down a substantial $100. The price of the versions of both models with more storage remains unchanged.

Increasing Volumes

"As we expand Kindle Fire HD 8.9-inch to Europe and Japan, we've been able to increase our production volumes and decrease our costs," said Dave Limp, vice president of Amazon Kindle, in a statement. "Across our business at Amazon, whenever we are able to create cost efficiencies like this, we want to pass the savings along to our customers."

The change comes as Apple's dominance in the tablet market it created is beginning to slip, with new models of Samsung's hit Android -powered tablets such as the Galaxy Tab and Galaxy Note squaring off against the iPad, now available in 9.7 inch and 7.9 inch options. Microsoft 's Surface and Google's Android Nexus are also making headway.

Kindle uses a specialized version of Google's Android operating system. According to just-released figures from research firm IDC, tablet shipments worldwide will grow 11 percent this year to 109.9 million, and Android's share will reach 48.8 percent. That would decline only slightly to 46 percent by 2017. Apple's share will drop below 50 percent for the first time this year with a 46 percent share, and down to 43.5 percent by 2017, IDC predicts.

The biggest growth predicted is for Windows, from 2.8 percent to 7.4 percent for Windows 8 devices and 1.9 percent to 2.7 percent for Windows RT-based devices.

Another firm, Localytics, which measures operating systems that access mobile applications, said last month that Kindle Fires make up one-third of Android-based devices globally and 56 percent of U.S. Android-based devices. The vast majority of Kindles, 89 percent, are in the U.S., the firm said

Despite the rationale of wider sales allowing lower prices, the cut is bound to raise questions about sales.

Sign of Weakness or Refresh?

"The question everyone is asking is simple," said technology commentator and consultant Jeff Kagan: "Is this a sign of weakness and lower-priced Kindles going forward, or is this a sign of an upcoming refresh?"

His conclusion: "Unless there is some big surprise, Amazon.com is just preparing for their upcoming refresh. Prices of existing devices often go down at the time of a refresh, not before."

Last year, Apple dropped the price of the iPad 2 16-gig Wi-Fi version to $399 ahead of its new iPad release.

"[Since there do] not seem to be any roadblocks to Kindle success," Kagan said, "I would say it's safe to attribute these price cuts to an upcoming Kindle refresh."

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