Kindle 2.5 update to counter iPad threat

Amazon has announced an update to its Kindle e-book reader in a bid to head off competition from the Apple iPad and Barnes and Noble's Nook.

The online book seller has released major updates for both standard and DX versions of its Kindle 2, adding the ability to share passages from users’ favourite titles on Facebook and Twitter.

Other new features of the Kindle 2.5 software include sharper fonts, two new font sizes and tools to arrange books into collections. The update also adds password protection for added security.

An announcement on Amazon’s web site explains the update has already been sent out to selected Kindle users. A full release is expected later this month, when updates will be sent wirelessly to all Kindle 2.5 users.

The update is not available to first-generation Kindle users. The most recent update for earlier devices is version 1.2.