There is an app on my smartphone which I have deleted it but in the very next day I found it again appear at the last app. I believe it autodownloads and installs itself. Is my phone being infected with virus? I'm not sure because it's a popular app, quite hot game: Little Alchemist, from a famous game site Kongregate:
https://play.google.com/store/apps/details?id=com.chinzilla.littlealchemist.google

I have deleted it again and it didn't return.