Det kan du godt....
We’ve been waiting for so long for this, Finally now we can use our iPhone as a USB Pendrive that too without installing any client-side application on our PC/MAC. All you need to install USB Drive app from cydia, and it is available for free. (Yes this is like USB Mass Storage coming to the iPhone / iPod touch)
Once USB Drive is installed you need to specify the size that you want to use as a USB Drive, Suppose you specify 1GB then that much of space will be allocated and will not be used by iTunes, its like as if you are creating a new partition, So do this carefully according to your usage.
IMG_0949 IMG_0952
IMG_0953 IMG_0954
USB Drive has 3 modes which are Default, Drive+iTunes and Drive only.
Default: This is iPhone default mode. USB Drive doesn’t install daemon application nor modify any USB settings. Picture Transfer Protocol (PTP) is active as well as iTunes synchronization and tethering over USB.
Drive+iTunes: In this mode USB Drive replaces PTP interface with Mass Storage interface and let you use iPhone as USB Drive. At the same time you can perform iTunes synchronization, developers can use XCode debugger, etc. In this mode USB Mass Storage will not work on Windows with iTunes or Apple USB Drivers installed.
Drive only: This mode is to resolve compatibility issue with Windows and iTunes. In this mode USB Drive changes iPhone device USB product ID. This will prevent iTunes synchronization, but USB Mass Storage will work on Windows (and other operation systems of course). Switching to the Default or Drive + iTunesmodes restores iTunes sync.
IMG_0955 IMG_0956
Everytime you select a mode you will be prompted for reboot to active the new mode that you had chose.
Note: In case you dont want to use your iPhone as Pendrive, so to free that space you can delete the partition, just by swiping on the drive name that you created.
IMG_0957 IMG_0951
Link:
http://iphonehelp.in/2009/10/07/usb-drive-converts-your-iphone-ipod-touch-in-a-pendrive-usb-mass-storage/