San Francisco (sans-serif typeface) and iOS 10 is a new variant named "SF Compact Rounded". It is used in the new contact placeholder icons introduced in the OSes. The "SF Serif" variant was showcased during the keynote at WWDC 2018 on June 4, 2018 when the all-new Apple Books app was introduced. This variant is exclusive to Apple Books in iOS 12 and macOS Mojave, is not mentioned in Apple's Typography design guidelines, and is not publicly downloadable like other variants of the San Francisco typeface. Since its introduction, San Francisco has gradually replaced most of Apple's other typefaces on their software and hardware
Helvetica add subtle differences. Substitute Helvetica designs that have survived into or originated during the digital period have included Monotype's Arial, Compugraphic's CG Triumvirate, ParaType's Pragmatica, Bitstream's Swiss 721, URW++'s Nimbus Sans and Scangraphic's Europa Grotesk. Berthold itself responded to Helvetica's popularity with Akzidenz-Grotesk Buch, effectively a Helvetica clone. Besides Helvetica imitations, Helvetica was available in custom derivatives with unusual special-order characters for many years, notably a straight-legged 'R' and round-topped 'A'. CNN uses a custom derivative, "CNN Sans", which has a '1' with a base. URW (later URW++) under the leadership of Peter Karow produced a modification of Helvetica called