What do the following actions in Xcode 4 do?
I'm not sure when to use each of these (or whether to use any of them at all).
Running is for running your app (on the Mac for Mac OS X, in the simulator or on the device for iOS).
Profiling is for running your app with Instruments (for finding memory leaks, bottlenecks etc.).
Testing is for running unit tests.
Archiving is building a distributable package of you app (incl. Ad-hoc iPhone distributions and upload to the App Store).