APPS
Full disclosure – I have never used a language-learning app as a teaching or learning resource. Having looked into them I see apps purely as a self-study activity, and as such their role in the physical classroom is negligible, especially when there are so many other interactive online resources available.
Nonetheless, I concede that language-learning apps are undoubtedly a popular free way to self-study English, and as such they should be included on this site.
With this in mind, I have reviewed the reviews.
Here are my recommendations for the most useful reviews of (free) English learning apps:

With over 500 million users, Duolingo is the most popular language-learning platform and the most downloaded education app. English is one of 39 different languages you can learn.
Read this review of Duolingo by Vikash Gupta on studyfrenchspanish.com

Ed Cooke launched Memrise in 2010, along with other Co-founders Ben Whately and Greg Detre. Like Duolingo and Busuu, Memrise makes language studying a game through plenty of fun activities. It has been available on Android and iOS since 2013, and there is also a browser version. After a decade of presence, the British language platform claims to have grown to over 40 million user bases in 189 countries.
Read this review of Memrise by Vikash Gupta on studyfrenchspanish.com

Bernhard Niesner and Adrian Hilti founded Busuu in 2008 in Madrid. The current headquarter is in London. After a decade, the platform has already developed a community of 120 million users.
After completing a placement test, learners study with flashcards, audio listening tasks and word puzzles. There are 13 different languages available to learn, including English.
Read this review of Busuu by Vikash Gupta on studyfrenchspanish.com

