With iOS 6 it’s a lot easier to ignore phone calls with a friendly message to the person that you’ll call them back later. You may or may not have noticed that now when someone calls you, there’s a small phone icon right next to the Slide to Answer button.
If you slide the little phone icon button up, you’ll see a list of new choices. You can still decline, like before, send a message to the caller if you don’t pick up the phone, or set a reminder for yourself to call the person back later.
If you pick either of the bottom two choices, Reply with Message or Remind Me Later, then the caller will automatically be sent to your voicemail. If you choose Reply with Message you’ll see a new list of options. The first three options with send the caller a text saying, “I’ll call you later,” “I’m on my way,” or “What’s up?”
If you choose custom, it will let you type in your own text message to send right then. If you want to change the default messages, just go to Settings > Phone > Reply with Message and type over the existing ones.
If you choose Remind Me Later instead of Reply with Message, you’ll be able to set either a time-based reminder or a location-based reminder to call the person back.
And here’s an extra tidbit. With the Reminders app on the iPhone, the reminders you add will be formatted with a link for the title so you just have to click the title and the person will be called back right from this app.