“We were hiding the game under all these layers,” Vollmer said. At one point veteran game designer Zach Gage sent them a “sobering” e-mail that said the art wasn’t working, and this acted as a wake-up call. What if the game didn’t need anything else?

“It looks like the entire time we were striving for simplicity and minimalism, and that’s not true at all,” Wohlwend said. “That’s just where we ended up going. The game resisted complexity because it was such a small game, it was four by four grid, and numbers, and just the four directions. It always wanted to be simple.”

Threes is a fantastic new iOS game. It reminds me in some ways of my favorite iOS puzzle game of all time, Drop7. It makes you feel like a smarty-pants if you are able to forecast several moves in advance. 

Also, their tagline is perfect: a tiny puzzle that grows on you.