The iPhone ebook reader app iBooks has been released on iTunes, now available for any iPhone running iOS 4.

iBooks has been available for iPad since the device was released in April, but has only just been made available on other iDevices, iPhones and iPod Touches, thanks to last night’s iOS 4 update. iBooks gives you access to the iBookstore, Apple’s own ebook shop.

The iBookstore is home to many free ebooks, including Project Gutenberg’s 30,000-strong selection of classic (and no-doubt not-so classic) reads. iBooks gives you a virtual bookshelf to check out all your downloaded novels from, and also lets you sync your own DRM-free ePub files using iTunes.

iBooks is available from iTunes now, for free. You’ll have to install the iPhone iOS 4 update first though, if you haven’t already.

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