Amazon is delivering on its promise of making ebooks more widely available. At this time, the same ebook service that is available on Amazon’s ebook reader, the Kindle, is also available on a select smartphone–the iPhone.

According to TUAW, the iPhone application will allow you to sync with Whispersync, the Amazon technology that allows you to pull books from the Amazon library and onto your device. However, you cannot buy books directly from the Kindle application. Instead, you must browse from any connected web browser.

The good thing: Smartphones now display crisp colors and color pictures and illustrations will show up in color rather than black and white like on the Kindle.

The bad thing: Right now the application is iPhone only. Hopefully other smartphones, including Windows Mobile, can join in on the action in due time. Also, hopefully Amazon will allow users to purchase books from other platforms. The theory that the purchase option isn’t available on the iPhone application is due to Apple’s tight control of application distribution; if that feature was included Apple may have rejected the application.