With the latest news of iOS 9 and OS X Yosemite 10.11, we’ve seen a new system font called “San Francisco” font and thankfully you can use it on your jailbroken iPhone/iPad or iPod Touch and even on your Mac.
STEP 1: Download BytaFont 2 from Cydia store.
STEP 2: Add a new repo to your sources: http://dbk1ng.myrepospace.com
STEP 3: After the repo is installed on Cydia store, search for “San Francisco iOS8″ and install it. The size should be about 19.8MB.
STEP 4: To install on your iPhone, just open BytaFont 2 and tap on “Basicâ€
STEP 5: Now choose ‘San Francisco font’ and it will respring your device..
After the respring you should see your iPhone font system is changed and here’s how it looks:
