I have not heard "free to enter" before, if I had to guess, they mean that the entry barrier is very low, because you are supposedly going to be able to play the game on your phone and they assume everyone has a phone so the game is free to enter as in you don't require a computer or a tv with a console to play.
From what we have seen it looks like Rene will probably be free to play with different ways of monetizing the game.
I'm not a fan of them making the game for a phone as well because I think that will just limit them in what they can make.
