How To: Install iPhone fonts (iOS 4)
You can install iOS 4 fonts manually via SSH or USB, since FontSwap currently does not handle them.
The very first thing to do is, of course, download one or more fonts via the Download (iOS 4) button (e.g. Hand of Sean) and unzip them; in each zip you will find: Helvetica.ttc, MarkerFeltThin.ttf, LockClock.ttf, PhonepadTwo.ttf, HelveticaNeue.ttc and PhoneKeyCaps.ttf (where available) and one or more license/readme files.
We suggest to always read the license files you may find: they can be html, txt, pdf or something similar.
The next step is to connect to your iPhone and overwrite the original fonts:
* go to the folder /System/Library/Fonts/Cache
* if you haven’t already done so, backup the default font files (Helvetica.ttc – MarkerFeltThin.ttf – LockClock.ttf – PhonepadTwo.ttf – HelveticaNeue.ttc – PhoneKeyCaps.ttf) to a safe place or rename them
* copy to /System/Library/Fonts/Cache the font files only, i.e. the ttc/ttf files mentioned above
* respring your iPhone (use SBSettings or simply select-deselect a theme in Winterboard and exit)
* ..done! Enjoy your new fonts!