This app was mentioned in 3 comments, with an average of 1.00 upvote
https://play.google.com/store/apps/details?id=com.runningpillow.HS
It's a game called cardstone, really fun! Maybe the STS devs were inspired by it?
Cardstone is kinda cool too
You know someone actually made a game called cardstone to cash in on that, right?
https://play.google.com/store/apps/details?id=com.runningpillow.HS