original paid games.
The Dollar Game - Eliminate Debts! (no ads; endless + custom levels). The Dollar Game is a little {maths} game in which you try to share money between people, so that they all are no longer in debt.

If you want to know what's exactly about, watch https://www.youtube.com/watch?v=U33dsEcKgeQ, a video from Numberphile, where they explained and introduced The Dollar Game to the world :).

Modes:
- custom, defining your own number of vertices, edges, and money in the system
- le