Aldiko, which appropriately stands for book in Swedish, Aldiko is an e-book reader application for the Android and iOS operating systems. It supports the EPUB format for digital publications and incorporates facilities for browsing online catalogs on thousands of books (including thousands of free public domain work) and downloading them directly into the user's personal library. The application features a bookshelf-like user interface that lets user navigate their collection of eBooks. It also provides a customizable reading experience through configurable font and background color, font size and type, margin size, display brightness, page turn mode, etc. Additionally, the application allows users to import their own books to read them on the go. Aldiko does not support font embedding. it comes in two versions; free and premium.
Obviously, the difference is the cost. the free offers the same books but with ads while the premium don't display ads and charge you $3.79 .
Both offers over 1.2 million titles. From bestsellers to literary classics coming from the world's largest publishers to indie publishing houses, and a very neat and modernized looking app but not much categorizing, yes it look simpler but lose a point for less categories.
Benefits.
support indie books
simple
free
a huge amount of free content
Very customizable
Drawbacks
Not much categorized
No diversity in content
no audio books
My view
It is a good app and offer much more classical books than eg.free books and very simple looking, I recommended especially in vacation. but ads may be a problem