Using GCD and Blocks EffectivelyWith iOS 4.0 Apple introduced two new technologies to the iOS platform: Grand Central Dispatch, and blocks. Simply put, it is to multi-threaded programming what fire is to a barbecue. Sure you can do without it, but the end result is much better. Despite all this, developers still seem to avoid using it. Some of the reasons for this, off the top of my head, could be backwards-compatibility for o
