After about three years of development, Google introduced the variable Roboto Flex headset. The typeface is a further development of Roboto, the default font in the Android platform, which was created with an eye on fonts from the neo-grotesque family such as Helvetica and Arial. The font is distributed under the SIL Open Font License 1.1.
The main feature of a variable typeface is the ability to flexibly change stylistic characteristics, for example, you can change the settings for the angle of inclination, thickness, height, indent and other parameters. Instead of a separate description of each representation of a glyph, in variable fonts, combinations of possible variants are specified through the definition of delta deviations from the base glyph, with the result obtained using interpolation and extrapolation. This allows the text to be as bold, wide, or narrow as needed. There is Cyrillic support (among the main font designers are Ilya Ruderman, Yuri Ostromentsky and Mikhail Strukov).
Source: opennet.ru