If you want to manually mask your image, here is updated code that works with retina screens
- (UIImage *)maskWithColor:(UIColor *)color
{
CGImageRef maskImage = self.CGImage;
CGFloat width = self.size.width * self.scale;
CGFloat height = self.size.height * self.scale;
CGRect bounds = CGRectMake(0,0,width,height);
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef bitmapContext = CGBitmapContextCreate(NULL, width, height, 8, 0, colorSpace, kCGBitmapAlphaInfoMask & kCGImageAlphaPremultipliedLast);
CGContextClipToMask(bitmapContext, bounds, maskImage);
CGContextSetFillColorWithColor(bitmapContext, color.CGColor);
CGContextFillRect(bitmapContext, bounds);
CGImageRef cImage = CGBitmapContextCreateImage(bitmapContext);
UIImage *coloredImage = [UIImage imageWithCGImage:cImage scale:self.scale orientation:self.imageOrientation];
CGContextRelease(bitmapContext);
CGColorSpaceRelease(colorSpace);
CGImageRelease(cImage);
return coloredImage;
}