Readlang is an eReader made specifially for language learners. It allows you to import books, articles and webpages, and has a unique swipe-to-translate feature allowing you to effortlessly read texts beyond your current level. All your translations are stored, along with their contexts, for you to work on memorising them later. Import articles to Readlang with the Web Importer. Available as a Chrome extension, or a simple bookmark, click this from any web page to import a plain text version of the article to Readlang. You can also input text directly or from a file, which can be the size of an entire novel.
I tested Readlang on a BBC News article, and as you can see from the screenshot below (if you speak French!), the results are mixed. It works well with single words which have one clear meaning, but not so well with words which have different meanings ('plot'), or lexical items consisting of more than one word ('in place'). However, you do have the option to change the translation on your flashcards, which you can do with help of an online dictionary. And if you sign up, you can also get the translation for phrases, which greatly improves performance. All in all, I'd say it's well worth giving Readlang a try, especially as it's free. You can find plenty of new reading material by using this page of links, and there's also a library of public texts shared by Readlang users. And see here for instructions on using Readlang on an iOS device.