(http://stackoverflow.com/questions/22345046/customize-button-shape-in-ios-7-1) Sub class the button and try which shape you want.... (answered Mar 12 at 10:06 by Spynet)

Customize Button shape in ios 7.1

#import "YourButton.h"
#import <QuartzCore/QuartzCore.h>

@implementation YourButton

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        // Initialization code
    }
    return self;
}

- (void)awakeFromNib
{
    [super awakeFromNib];
    CALayer *mask = [CALayer layer];
    mask.contents = (id)[[UIImage imageNamed:@"ge.png"] CGImage]; // ge is the black & white png image
    CGSize size = self.frame.size;
    mask.frame = CGRectMake(0, 0, size.width, size.height);
    self.layer.mask = mask;
    [self.layer setMasksToBounds:YES];
}

@end