Game to learn English - EnglishTracker

"You have to spot the mistake. If you get it wrong, you receive a clear explanation. It’s fun and easy to play." (An article on the blog of the British Council about the five most usefull free apps for learning English)
"A well thought out system of progression, good explanations" (AppGratis)
This app is ideal for false beginners and advanced users who already have a good basis in vocabulary, but who need to work on their grammar. True beginners should use EnglishTrackerKids, which is also available from this App Store.
You are preparing for an exam, you're not comfortable in writing an e-mail in English. You have tried all possible methods to learn your grammar but nothing works! Here is a new type of simple and effective training to boost your English grammar.
Read the sentences, find the errors. To level up, you should master 5 grammar rules. Every sentence that artificial intelligence shows you corresponds to one of these rules. But which rule is it?
You earn a star when you master a new grammar rule, you lose a life if you make a mistake. The more you make mistakes, the more the artificial intelligence will be demanding! Will you manage to complete all the levels?
2000 examples, 100 essential rules of English, 20 levels, 3 modes of learning.
The first 4 levels are totally free: 20 basic rules to absolutely know (400 examples), ideal for beginners.
The rules are translated into English, French, Spanish, Korean and Russian by human translators (no machine translation).