I am posting two links about the title. This may give more insight to the developers of Fontself and those who create fonts using Fontself with the intention of providing fonts that should render correctly on the devices .
Samsung Devices and their font anatomy
Thank you for the links. However, as a developer of a character set, you have no influence on how it is rendered on (other) systems.
As a programmer - not of Fontself - I can tell you that it is very tedious and time-consuming to react to errors or unexpected behaviour of other software (e.g. renderers). Especially if there is no documentation.
I am not trying to influence anyone just some information I was trying to share.