It took me a fair amount of time to research about that. Unfortunately, there isn't. However, there good tools that I know, because I'm also learning Mandarin. If you are still active on renshuu, and are interested, please let me know so I can send you the links.
I think there isn't any app so good like renshuu. But other apps for learning mandarin which has gamified interface is Hello Chinese or Duolingo. If you are not looking for a gamified interface then you can make flashcards in anki and use pleco for dictionary. Also watch you tube videos for whatever language you want to learn. In Chinese, the main difficulty is the tone. With a small change in tone, the meaning of the word only changes. Anyways, I hope this small writing of mone will be helpful. Like this if you really find this helpful ❤️