Frame with 50 png in iPhone

I have a ViewController with 16 buttons. Each button loads a popover that show 50 frames renders in moving.

What is the best form to do it?

I know that imageWithName is bad because it load all images in cache, and for this reason im doing it with:

myAnimatedView.animationImages=[NSArray arrayWithObjects:
                                 [UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:@"%@0000",nombrePieza]ofType:@"png"]],
                                 [UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:@"%@0001",nombrePieza]ofType:@"png"]],
                                 [UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:@"%@0002",nombrePieza]ofType:@"png"]],
     ...
     ...
     ...                         [UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:@"%@0050",nombrePieza]ofType:@"png"]],nil];
 

But when i load about 10 times the popover with differents frames, i have a leak of memory only on my device, but not in the simulator.

For this reason, i want know which is the best form to do it?

With a video? or with CAAnimation?

Thanks for help.

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