I would say XCode 4 are making the whole programming experience in iOS a complete other experience. As for me, coming from database and visual basic, I'm at home in the XCode 4. I was not in the earlier the earlier versions.
I will show you a trick which you can impress however with XCode 4. Start it, chose a "Navigation-based Application", press next, give it a name and keep shure that "Use Core Data" is checked. Press next and then press create.
Now you're into a full database app. Just pres cmd+r to run it, and you have a database app with add, edit, delete and swipe.
This is impressive. It's a bit harder to go to next step however…
Earlier this summer I wrote iPhone programming – with XCode 4, it's so easy that even a CEO can do it!
Now there has come some new Kindle books on programming Core Data on XCode 4. I'm churning through the newest one "Core Data for iOS – Developning Data-Driven Applications for…"
Stay put, I tell you more…