Very nice game. I just played through it twice there. I didn't find having to roll a 6 too bad but I guess you could get very unlucky.
I think there should be an 'are you sure you want to quit?' warning when you press the board horde button. It's not obvious that touching that takes you back to the main menu and I imagine if you had two players playing opposite each other on a tablet, it would be very easy to accidentally end your game.