[allan_s]

does it have some connections (in term of inspiration/algorithm etc.) with speakgoodchinese ? (an opensource project to help practice tone)

http://www.speakgoodchinese.org/ https://robvanson.github.io/sgc3/

[reubenbond]

Great! We need more freely available, open-source language learning apps. I made one for reading/typing mandarin on Android: https://github.com/ReubenBond/HanBaoBao / https://play.google.com/store/apps/details?id=com.tallogre.h...