This chapter covered lots of ground, and you've now toured nearly all the standard gadgets supplied out of the box by the iPhone code toolkit. A handful remain, though, and you'll dig into these later in the book:
Activity indicators and progress bars. See Yep, I'm Working on It and Bending Time: Progress Bars and Other Distractions.
Alerts and push notifications. See When To Interrupt and Pushy Notifications.
Map views. See Roll Your Own: Browsers, Maps, and Email.