If you buy downloadable versions of the upcoming Call of Duty on PS3 or Xbox 360, you can advance your warfare onto PS4 or Xbox One for free. That’s the deal Activision’s offering until March 31, 2015: customers who purchase a “Digital Edition” of the last-gen version of Advanced Warfare can upgrade to the current-gen version at no extra cost. So if you buy it on Xbox 360, you get the Xbox One version for nada and you still retain the 360 license, meaning the Xbox One version is essentially a bonus freebie.
The deal is slightly different on PlayStation platforms in that the shooter is now a Cross-Buy game. That means the offer works in reverse. So if you buy Advanced Warfare on PSN for PS4, you can also download it on PS3, as well as vice-versa.