It's an app.
Some money could possibly be made by some people legitimately.
The bleakest part is people who didn't recognize how extreme a gamble it is if that's what somebody wants to pin their entire livelihood on.
Whether they wrote the app or not.
The "house" just drew the winning hand, and all the gamblers lost everything they had on the table at once.
That can happen at any time, and almost always happens eventually, that's why they call it gambling.
It's not so bad if you don't bet everything.