It’s now possible to combine all your favorite Wikipedia articles into an eBook and read it offline on any of your favorite (oops! I said that twice) devices.
You'll find enough tools offered by Wikipedia to help you create eBooks using content from Wikipedia pages.
The PDF export option has been on offer for quite some time now. However, exporting the pages to EPUBs is a better option, since they are friendlier with mobile phones and tablets. PDF will never lose its demand, since its print-ready.
Steps to convert Wiki's into an eBook
1. Open your favorite Wikipedia page and select Book Creator from the toolbox menu. You can alternatively use this link to open the Book Creator.
2. Next click the “Add this page to your book” link.
3. You may also choose to hover your mouse pointer over any internal wiki link to add the linked page to your eBook, this doesn't require you to unnecessarily open the page.
4. After adding all the pages you needed, click the Show Book link, name your eBook and download it.
iOS users can view them inside the iBooks app, while Android users can choose any eBook reader that supports ePUB format.
Wikipedia articles come under the Creative Commons (share alike) license. So it shouldn't be an issue distributing these eBooks.