"spartan assault" was released in north america and europe on july 18 and 19, respectively. in the united states, the game was initially restricted to verizon phones before being released to all windows 8 enabled devices. an xbox one version of the game released on december 24, 2013, followed by an xbox 360 version on january 31, 2014. it was released on steam on april 4, 2014, the first game in the series to be distributed on the platform. on april 16, 2015, the game was released for ios. the game's release coincided with a tie-in comic series, "halo: initiation", which detailed palmer's path to becoming a spartan.