Google has announced that its Picasa photo sharing service now explicitly supports the iPhone:

“After you go to Picasa on your iPhone and log in, you can quickly see all your albums that you’ve uploaded to Picasa Web. If you click on any of the albums, you can get a full view of your picture with comments from your friends. Or you can click on Slideshow, sit back and watch the pictures scroll. You can also search for photos in your album or through community photos. Finally, with one of my favorite features, you can view your friends’ albums through favorites.”

Google automatically recognizes iPhone/iTouch users and formats Picasa for the smaller screen.