Awesome

This category allows you to resize an UIImage at a constraint size, or proportionally so that it fits in a given CGSize.

This category defines the following methods :

-(UIImage*)resizedImageToSize:(CGSize*)size;
-(UIImage*)resizedImageToFitInSize:(CGSize*)size scaleIfSmaller:(BOOL)scale;

This methods takes correctly the imageOrientation / EXIF orientation into account.