They apparently helped out with the online infrastructure too.
The DualShock 4 has been an iconic design that Sony consistently used for three generations of PlayStation consoles straight- people didn’t expect Sony to come out and change the design for the PlayStation 4, but they did, and in the process, they created a controller that many feel is the greatest ever made, right up there with the Xbox 360 and Gamecube controllers. At the very least, it is a supremely comfortable controller for modern, action games.
And as it turns out, Bungie, the guys who helped popularize shooters on consoles in the first place with Halo on Xbox, helped Sony develop it and make it better for shooters.
“We really didn’t know where anybody was going,” Bungie’s Eric Osborne said in an interview with TechRadar, “but it became really clear talking with Sony at the outset that their vision really aligned with where we wanted to go.”
He added, “They worked with us, of course, on core systems and the controller itself – making it better for shooters, helping improve that for players, helping include and improve the social aspects of the game.”
So it seems like not only did Bungie help out with the controller design, they may also have advised Sony on the online infrastructure for the PlayStation 4. It shows, really- the guys who popularized both those things on consoles helped Sony, and helped them to catch up to the competition.