NEW YORK -- Frommer's travel guides are becoming available for download to iPhones and the iPod Touch.

Digital editions of Frommer's 2008 guides to New York, San Francisco, London and Paris are $9.99 from Apple.com via the new Apple App Store and from iTunes.

More Frommer's guides will be out later this year for downloading.

Once the books are loaded, users can browse ad-free content without an Internet connection. The format also offers interactive maps, Web and phone links through the touchscreen interface.

To view a demo of the application, visit http://www.frommers.com/go/mobile.

The applications were developed by Modality, which specializes in transforming content for handheld devices.