It is now 100% sure that Monstro will be released 10th January 2014!
The expected price is going to be somewhere between 3 and 5 USD, + $2 for the soundtrack in lossless format. In the initial release the game will be only available on Windows (due to no Mac machine to build the final product) as an installer. Currently the plans for mobile release are abandoned but the game is pretty much ready to play on tablets in its current state.
Stay tuned!
