Apple Watch uses an in-house font San Francisco, designed by Apple for better legibility on a small display. Sources close to the company say that the company-designed font may soon appear on iOS and OS X devices.

The San Francisco font used in Apple Watch was designed with the factors Text and Display. Display is more applicable to texts in 20 points or larger while Text works best for smaller screens like the Apple Watch. The font type was designed particularly for better legibility on the small interface of Apple Watch.  However, sources say that the company is planning a system-wide implementation of the new font.

Apple is planning to use San Francisco in place of the current Helvetica Neue in iOS and OS X Yosemite system font. If the plan will push through, it will effectively replace system fonts for iPads, iPhones and Macs on iOS 9 "Monarch" and OS X 10.11 "Gala."

Apple officials reportedly believe that the change could help refresh its operating systems and avoid it from becoming outdated. Some Apple watchers are skeptical about the rumored change particularly with the timeline the company currently has. Experts believe that Apple might need to make changes on its apps to make sure the new font will fit. As a result, additional testing and quality assurance will be required.

Despite doubts about San Francisco, the font has already made its way to the new MacBook keyboard. Some supporters of Apple's freshest font have already applied it to their OS X devices and they like the change so far. Experts also admire the thought that Apple designed a particular font inspired by utility and purpose over style.

Apple has always been known to have top of the line designs and some say that the company went overboard when it chose Helvetica Nueu's seamless characters despite its poor readability.  Changing for purpose over style is yet another admirable and contemporary move from Apple.