The developers at Smile Software have been hard at work on PDFpen for iPhone for some time. Tonight it went live in the App Store. This version is built just for the iPhone and iPod touch screens and looks great. Moreover, it has all of the features I love about PDFpen: iCloud Sync, Dropbox Sync, easy annotations, text substitution, and a user interface for humans. Using iCloud, I now have my key PDFs in my pocket.
How much do I like it? Enough to make a video.