Marvin is a feature-packed and extremely configurable iOS reader app for DRM-free EPUB files. As a reader, Marvin comes packed with great reading features, from a variety of fonts (including a specialty font for dyslexic readers), a night mode and customizable themes, highlighting, annotation and dictionary tools. You'll also find numerous format tweaks ranging from text justification, to paragraph indentation and spacing. Marvin comes with a solid set of organizing tools, allowing you to sort into collections, choose from list or cover views, collection sorting and more. Extremely configurable and feature-packed, Marvin's main downside is that it's zeroed-in on EPUB reading, and supports no other formats.