How can I change image tintColor

Try to generate new image for yourself

UIImage *newImage = [_sketchImageView.image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
UIGraphicsBeginImageContextWithOptions(image.size, NO, newImage.scale);
[yourTintColor set];
[newImage drawInRect:CGRectMake(0, 0, image.size.width, newImage.size.height)];
newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

_sketchImageView.image = newImage;

And use it.

Good luck

======= UPDATE =======

This solution will only change color of all pixel’s image.

Example: we have a book image: http://pngimg.com/upload/book_PNG2113.png

And after running above code (exp: TintColor is RED). We have:

SO: how your image is depends on how you designed it