How to transfer files to and from my iPhone?

How can I transfer files to and from my iPhone?

Just plug it in with the normal USB sync/power cable.

It should appear as a drive on the computer after a few seconds.
(Close itunes if that starts.)

It's no different to plugging in a USB memory stick.

Looking in that, you will see the DCIM directory that contains the photos taken with the phone camera (that's how you copy photos off).

Just create another directory (folder) to store your files.

Note that you can't access these files on the phone itself, it is purely a storage area.

Anything that needs to be accessible on the phone itself has got to be downloaded by it or transferred by itunes - apple don't allow direct access to the "working areas" to avoid the chance of any critical parts getting over-written or corrupted.

You can transfer them only by using a USB cable, and then connect your iPhone to the other devices, such as a computer or a tablet, so that you can transfer or receive any files to or from your iPhone.

Basically, I'm trying to use it as a flash drive, where I can put some portable apps on it, PDF files, Word documents, etc, and be able to access them on my iPhone as well as easily transfer them from one computer to another

With itunes