Though it is not necessary to buy anything to learn a language, you shouldn't be afraid to spend a bit of money. Apps will generally be free, but premium editions remove ads and add a few features. Generally, you can expect 90%+ of the same functionality when using the free version and most commercial programs have free alternatives as well.
Keep in mind that when learning a language, there is no ultimate source of knowledge. No resource is perfect alone. For this reason you need to constantly be looking for new sources to learn from. Have one book for grammar, one book for idioms, a dictionary or two, a couple of books for script learning. Watch some tv and listen to some music. Like lots of other skills, language learning requires a complete package of tools. However, language software can also provide you with a good overview of a language’s basic structure.
|Duolingo||Desktop, iOS, Android, and Windows Phone||Free, $10/Mo.||Contains a variety of speaking, listening, translation, and multiple choice challenges covering many aspects of the language. Duolingo Effectiveness Study and more research here.|
|Lingvist||Desktop, iOS, and Android||Free, $20/Mo.||Flashcard system that uses statistically relevant words and phrases to aid memorization. Very good progress tracking, stats and audio quality.|
|Clozemaster||Desktop, iOS, and Android||Free, $8/Mo.||Similar to Lingvist in that it promotes memorization through the use of context and word association hence "cloze" (see: Cloze test).|
|Memrise||Desktop, iOS, and Android||Free, $9/Mo.||Pre-made and user-generated flashcard decks (over 20 million users). Corresponding courses for Assimil, Duolingo, etc. are available|
|Lingodeer||Desktop, iOS, Android||Free, $9/Mo||Similar to Memrise and Duolingo. Specializes in Asian languages.|
|JW Language||iOS, Android, and Windows Phone||Free||Made by Jehova's Witnesses for the purposes of missionary work. Has a really cool interactive grammar section which teaches the user my manipulating a sentence in various ways.|
|LingQ||Desktop, iOS, and Android||$10/Mo||Input (reading and listening) focused product. Plenty of user-generated content, but it is difficult to navigate. Import feature works well. Warning: Website makes it difficult to unsubscribe and delete credit card information.|
|Learning with texts||Desktop||Free||Very similar to LingQ. Difficult to install.|
|Wordic||Desktop and Mobile||Free||Use Wikipedia articles or Youtube videos to learn vocabulary. Similar to Lingq, but without user-generated content and no subscription.|
Courses & Programs Edit
|Assimil: "with ease" series||Audio + Book||$125||This method is focused on learning whole sentences, for an organic understanding of the language. Can be used to learn the basic rules of grammar and vocabulary of 2000-3000 words|
|Pimsleur||Audio||$575||150 30-minute lessons with a focus on speech and conversational ability. Try a free lesson!|
|Michel Thomas||Audio||$35-$125||Developed by Michael Thomas -- a well known Polish polygot. Michel Thomas teaches you grammar: how to use verbs. You'll have the skeleton of the language in your hands but little vocabulary.|
|Language Transfer||Audio||Free||Very similar to the Michel Thomas method, but free.|
|Rosetta Stone||Desktop||$20/Mo.||Covers pronunciation, reading, listening, vocabulary, writing. Can be used as a beginning tool but is generally considered overpriced and ineffective.|
|Sharex||Windows||a free and open-source screenshot and screencast utility. good for capturing audio/video clips for anki cards|
|Netflix||Desktop, Mobile||$13/Mo||First switch Netflix to your target language in profile settings. Then pick a show with descriptive video and also use the LLN addon if you want to.|
|Anki||Desktop, iOS, and Android||Free, $24.99 on iOS.||Popular flashcard software with user-made decks|
|subs2srs||Desktop||Free||Allows you to make large anki decks using .srt and video files very quickly. Guide|
|Vocabulary Tester||Desktop, Mobile||Free||It can be used to learn how many word you know. It's a vocabulary size estimator. Also, there are many vocabulary exercises by category and level.|
|Wiktionary||Super useful website for understanding words on a deeper level (origin, roots, etc.)|
|Linguee||a bilingual dictionary for a number of language pairs, including many bilingual sentence pairs. really good for generating numerous sentences for any given word. same creators as DeepL|
|DeepL||One of the better online translators. Better than google but only supports 8 languages.|
|Google Translate||Fast, easy to use and has the most languages of any translator. Not all have full support, and even in popular langs it can make big mistakes.|
|Bing Microsoft Translator||Seems about as good as google, but with fewer languages.|
Reading materials Edit
Gutenberg project - Site with free public domain ebooks in a bunch of languages.
Wikibooks - Free public domain books in a lot of languages, including some obscure ones.
libgen.io - Free safe downloads for books, including many for languages.
/Lit/ wiki - /lit/ literature wiki, lists some foreign-language books and methods for finding books.
Listening materials Edit
Librivox - Collection of public domain audiobooks.
Easy languages - interview-type videos in many languages.
/Mu/ wiki - The /mu/ music wiki, lists some foreign-language music and the methods for finding new music.
Language exchange Edit
Language exchange apps are apps that "match" people who are learning each others language so they can practice in each others language.
|italki||Desktop, Android, iOS||Free|
|TL gf||real life||??|
|Radio Links||Flash Games||Other Resources|
|http://tunein.com/||http://www.digitaldialects.com/||Wordle is a word cloud
Lists of most frequently used words, very useful for deciding what vocab to learn