You can use iTune to transfer pictures, songs, vidoes to you iPhone. But it does not sync other file types. The iPod used to function like a external storage, this functionality is however removed from iPhone. I do not know why Apple do that. If they are concern of privilege abuse, they can lock down the access to specific folder only. Like what Sony Ericsson is doing – on my P900 and P990i, I could only access specific folders from both the phone and my PC.

You can however transfer Microsoft Words, PDF files to your iPhone via email. Just configured your Mail on iPhone to sync with, say, Gmail, and send those file to this account. The attachment would be kept in your iPhone, provided you click on the “All Mail” category to download the mail to your phone, and click on each attachment at least once to download it.

Note however, Unicode file name is however not working in this case.

The following is a list of supported file types in email attachment.

.c, .cpp, .diff, .doc, .docx, .h, .hpp, .htm, .html, .m, .mm, .patch, .pdf, .txt, .xls, .xlsx

[ Update 10 Sep 2008 ] Now there is another way to transfer files to your iPhone without using the above method, or Jailbreeak it. There is a software “Air Sharing” available from Apple AppStore, free for a limited period of time. This is the summary of how Air Sharing work:

  1. Connect your iPhone to a wireless network which your PC is connected to.
  2. For PC (XP), set up a connection from “Network Connections” to http://your-iphone-ip-address:8080
  3. A connection will be established with your iPhone, locked to the root folder of Air Sharing, and you can read and write file into this folder.

For Vista or Linux or Safari, there is a clear instruction on how you setup the connection. It work great for me!

Do have security in mind however. The sharing is turned on by default. If you do not want to transfer file, do remember to turn off the sharing.