Additionally there are three margin adjustment settings, which seems kind of pointless because they make margins larger instead of smaller. (blog.the-ebook-reader.com)
Text Adjustment: All Kobo ereaders offer line spacing and margin adjustment for ebooks. (the-ebook-reader.com)
«But if you look at what happens on the shelves in the supermarkets, the differences aren't as apparent because the supermarkets do a lot of work in margin adjustment to try to keep the offering to their customers fairly consistent.» (afr.com)