UPDATE 7.30pm: Respawn has clarified to Eurogamer that Sony actually asked for it to develop a version of its R1 project for PlayStation Vita, not the finalised Titanfall game.

As the Final Hours app explains, R1 was the code-name for Respawn's in-development project at the time - it took several more rethinks before the studio finalised the Titanfall game we know today. Here's the relevant paragraph from the app:

"Armed with the specs for the Xbox Durango platform, Respawn pushed forward on game development. At the same time the team quietly reached out to Sony to see if it could share any information on the next PlayStation, another target platform. Respawn quickly found out that Sony wasn't ready to talk about its plans for PS4. Instead, Sony offered to help with developing a version of R1 for the handheld PlayStation Vita platform."

ORIGINAL STORY 11.07am: Sony originally pushed for a PlayStation Vita version of the now-PC and Xbox 360/One exclusive Titanfall.

Developer Respawn reached out to Sony before Titanfall's exclusivity agreement with Microsoft was signed to discuss PlayStation 4 target specs, but was told the platform holder wasn't ready to divulge the details.

Sony suggested a PlayStation Vita version instead, and offered to help make it.

The new details come from Titanfall's Final Hours App which has just been released for iPad, Windows Surface and on PC/Mac via Origin, excerpts from which have been posted online (thanks, Gamespot).

Activision's bitter lawsuit with Respawn over the departure of co-founders Vince Zampella and Jason West is covered in detail - "almost half the company" would regularly be pulled away from development for multi-hour legal meetings with lawyers.

"Often those discussions would spill over into the afternoon with debates about the latest legal maneuver," the app's author Geoff Keighley writes, in an excerpt published by Kotaku. "The rest of the company was supposed to be heads-down working on the game, but one Google Alert about the lawsuit sent development into a tailspin for the rest of the afternoon."

The legal battle contributed to the souring of relations between Zampella and West, which - along with some personal issues - led to West's departure from the company.

"What West hoped would be a constructive dialectic turned into an all-out lynching," Keighley continues. "Pent-up feelings burst into the open. Employee after employee complained about the rushed way the lawsuit had been settled. Many attacked West directly and complained that he hadn't properly balanced his time between the lawsuit and the game, which he had largely ignored for the better part of a year."

Other tidbits revealed include the fact that, up until 13 months ago, players would begin matches in Titans and only spawn as a human Pilot after they had died.