A big part of Apple's Playgrounds is how it shows you the value produced by every line of code, shows how many times loops were executed, and allows you to view a complete history of the values any particular variable took on during a loop. This is hard to accomplish, as it requires modifying the compiler to output instrumented code (and it's also why Swift playgrounds don't execute very fast). This Objective-C version doesn't appear to do any of that. It looks great and that's not meant as criticism in any way, but it's not reasonable to take this and turn it into some Apple bashing.