Most of the chapters in this book focus on the data-related features of iOS and its devices: Wi-Fi, apps, the Web, email, photos, and so on. That's apt because our iOS devices are computers, after all, so it makes sense to concentrate on troubleshooting computing tasks. But the iPhone is different. Sure, it makes an excellent mobile computer, but at its heart it's also a mobile phone. And while it's true that the phone call is beginning to feel more than a little like an anachronism, the "phone" part of this smartphone is still used by almost every iPhone owner, even those in their twenties. (A recent Pew Research poll found that 93 percent of smartphone owners aged 18 to 29 had used either voice or video calling.) The phone call's enduring appeal comes from a number of factors: it's immediate (assuming the other person picks up!), intimate, and efficient. But all this only applies if the iPhone's calling features are working properly and you know how to get the most out of them. This chapter looks at a few common calling concerns and shows you how to fix them or work around them.