PikPok's Into the Dead 2 has been downloaded more than hit six million times in its first week of release.

The endless runner FPS is a sequel to App Store Editor's Choice smash hit Into the Dead, which was released in December 2012.

It has a fair way to go to catch its forerunner though: the original game has been downloaded more than 75 million times to date.

Into the Dead 2 may get there, though; it promises an evolving narrative, deeper gameplay, and highly crafted levels, offering players even more of an immersive and action-packed experience than the fan favourite original.

"The launch result for Into the Dead 2 has been amazing," said PikPok managing director Mario Wynands.

"Gamers have really responded to the high production values, compelling story campaign, and intense action. It is a very satisfying result on the back of a long road of hard work for the team, and it opens up a lot of opportunities for the franchise.”

Into the Dead 2 is available for free on iPhone, iPad and iPod Touch from the App Store, and on Android from Google Play.