San Francisco is the name of the new font used in Apple Watch. Apple designed this new font to make text read well on the small smartwatch screen. Rumour is Apple will use San Francisco as the system font for next version of iOS and OS X, replacing Helvetica Neue. Take a peak at typedetail.com to find out how the font would look on your desktop and phone. This font name might suggest the name of next version of OS X: OS X San Francisco.