Based on what I've read about the Lexend font, it is a most readable font.
I have been using Lexend as my default font on my ereader until someone pointed out that it doesn't have bold or italics versions. Unfortunately the font creator didn't create a bold or italics version of the font, nor is it a priority for him.
So, fellow readers, what is the second-best readable font? I want to use a font that has been trialled and put tot the test the way Lexend has? What do you all propose?