I am aware that there is no Android app for renshuu but today I saw that there is one installed on my phone. I opened it and it actually works, but I'm really confused with why it is on my phone because I did not install anything. is it some kind of malware?
I have the same, but this is not malware but rather a functionality of Chrome and/or Android. I used renshuu via Chrome on my phone until at some point it asked me while opening renshuu if I wanted to add it to the homescreen or something similar. Since then I now have the same icon on my phone and opening it opens an instance of Chrome that starts out on the renshuu page without an address bar.