Applying blue color effect to a picture

Can we apply some blue color effects to photo taken by iPhone or iPad programatically.

Like what we achieve using blend 开发者_如何学编程modes (eg. hue) using a blue color layer with any image in photoshop.

there's a couple of ready to use image manipulation routines like http://code.google.com/p/simple-iphone-image-processing/

or you could try to mess with UIImage

Found an article.

How would I tint an image programmatically on the iPhone?