The ball moved when he hit the ground, and acoording to the NFL rules.
A forward pass is complete (by the offense) or intercepted (by the defense) if a player executes a three-step process:
secures control of the ball in his hands or arms prior to the ball touching the ground;
and touches the ground inbounds with both feet or with any part of his body other than his hands;
and maintains control of the ball after (a) and (b) have been fulfilled, until he has clearly become a runner (see 3-2-7 Item 2).
So, essentially, a player needs to collect the pass, have both feet inbounds (or have a knee, butt, elbow, hit the ground inbounds), and keep control of the ball. Seems simple enough.
And yet, here we are in the Super Bowl debating what in the hell makes a catch. Jerricho Cotchery appeared to collect a ball and take it to the ground with the ball not hitting the turf. However, officials declared that he did not fully control the ball all the way through the catch – both in the official call and after a replay. Debatable.