title_body: Installing own font & using it to read ebook
upvoted_answer: Kobo ereaders are known for their font customization capabilities. They have a dozen of preinstalled fonts, and a couple of them aimed exactly to dyslexic readers.
  Besides selecting the font, you can also tweak it to your needs with many options for dimensions, spacing, margins, justification and thickness.
  
  You can read a couple of reviews, here and here, that explain these features with pictures so you can see if this is what you need.
  
  On Kobo ereaders it is also easy to add custom fonts, we already have a question on this site that explain how to do it.