The iPhone has no built-in BitTorrent client yet, but you can use it to access uTorrent remotely from anywhere in the world. The iPhone web interface for uTorrent makes it easy to manage your torrents when you’re away from your desktop computer.
The iPhone UI for uTorrent can be used to access uTorrent from your iPhone when you’re away from your computer. The interface is optimized for the iPhone and uses the regular uTorrent WebUI. At the moment the iPhone UI lets you pause, resume and add new torrents.
The iPhone UI also shows some status info such as the download/upload speed and the number of seeds and peers connected to the torrent, which should be sufficient to track the progress of your downloads.
The features of the iPhone UI for uTorrent are nowhere near those of the regular WebUI, but it does run smoothly on any iPhone. It requires the uTorrent WebUI to be installed in order to get it running, detailed installation instructions can be found at the iPhone UI homepage.
If you want to run uTorrent on a mobile phone other than the iPhone you could give uTorrent mUI a try. It looks less sleek than the iPhone UI, but the interface will allow you to remotely control your torrents from just about any mobile browser.
Perhaps it’s time for Apple or other iPhone developers come up with a full featured BitTorrent client for the iPhone?