Why only OS4.1 Support?!

I cant see the reason why users who do not want to upgrade to OS4.1 for some reason, cant play it? It is not sth outstanding and difficult! It is quite nicly made puzzle game so I dont understand why it cannot be played with earlier OS as it did before.
One start for not having support for OS older than 4.1

Dasha1405 about Gas tycoon 2