The graphic-heavy site (www.mobile.lonelyplanet.com) is accessible via an xhtml browser only and has been optimised for the Nokia 3650 handset.
It offers a mobile travel guide to over 40 cities worldwide with reviews, prices and contacts for hotels, restaurants, shops and places of interest.
Lonely Planet gained advice from Nokia on download times, use of colour and icons.
Nathan Clapton, business development manager Europe at Lonely Planet, said: "Up until now, WAP hasn't been a viable option, but with the new colour screens and faster downloads it has become an important space for us to be in."
The site is currently free to access, but Clapton said that the company would be looking to charge for mobile content in the near future.
Nokia is promoting the new site through bookmarks on its mobiles and by emailing details to members of Club Nokia.
Lonely Planet already offers content optimised for the Palm Pilot in the form of a 250-page guidebook covering more than 22 cities worldwide, CitySync, which it launched in 2000.
CitySync users pay $19.99 (£12.46) to download data on one city or $49.95 (£31.13) for a cartridge containing information on 20 cities.