UIImage-Mask
The best way to make a square picture into a circular one.
How to use
#import "UIImage+Mask.h"
UIImage *image = [UIImage imageNamed:@"someImage.png"];
UIImage *circleImage = [image circleImage];
Why not use CALayer
You can use CALayer If you only have A view needs to be rendered.
If there are many views (more than 20 maybe),that would be a nightmare :(
The easit way is the best way.Just generate a circular one.