The game is indeed built with Unity. 3D models and animations were created in 3DS Max.
Game development was a hobby for me for a long time, with most of my experience coming from participating in 48 hour game jams, like the LD48. (http://www.ludumdare.com/) It's been an interesting journey transitioning a hobby project into a commercial release.
An interesting challenge that our team faced was that we all came from a programming background, so through the project we have had to find ways to fill all of the other requirements for the game.