Can Someone Help Me Understand This?

I have seen this game being published by so many people over the past year on Google Play Store:
https://play.google.com/store/apps/details?id=com.dhinsdk.universewar.battle
Can someone help me with understanding how that is possible? It doesn't seem like it's the same people doing this. Can someone help me find this sort of service or help me with understanding what this process is called where same app is being sold by different people?