The free games for Xbox One include Inside, the jewel-based platform from Playdead, available for download throughout the month & the Big Crown: Showdown party game for four players, which can be downloaded from 16 July to 15 August.
As for the Xbox 360 titles backward compatible with Xbox One,Castlevania: Symphony of the Night(from 1 to 15 July) and The Robinsons: A Space Family (16 July to 31), a tie-in to the eponymous Disney animated film.
Inside ( 1 July – 31 July)
Big Crown: Showdown (16 July – 16 August)
Castlevania: Symphony of the Night (1 July – 15 July)