After playing the game for a while I think it is remarkable in its depth and specificity of vocabulary. I've learned through error that you can really harm fluency by including any trace of L1 in your vocabulary practice, and this product seems to solve that problem.
As other comments have pointed out, there's a lot more to learning languages than vocabulary, but this looks like a really good implementation of an important piece of the process.
As other comments have pointed out, there's a lot more to learning languages than vocabulary, but this looks like a really good implementation of an important piece of the process.