It’s a new tweak.If you want to change the default font on your iPhone a new option has came.BytaFont, a new jailbreak application that allows you to easily change the font on your iPhone, system wide.
Follow the simple instruction to change it.First you need to install BytaFont from Cydia. Once this is done, go to Cydia > Sections > Fonts, and install any fonts from there.
Then go back to your iPhone springboard and launch BytaFont. You will see your downloaded font in there, as well as the original iOS 4 font (which comes preloaded with BytaFont). Select the font you want to install and confirm. Your device will respring and you should see the new font all over your iPhone.
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