Comment by snielson
Assistive access mode for an iPhone is fantastic for the elderly. It's the only way my 85-year-old father can even use a phone. One of the best features is that it can be set to allow incoming calls only from people in his contacts. It's such a lifesaver.
What if it's police or the hospital trying to call?
I suppose it'd be "simple" for the device to answer the call and then prompt for a password before ringing for the user, but then the random caller needs to know the password. But then again, it could be as simple as "This is Siri, please say the name of the person you're trying to reach.", and since spammers usually don't have a name associated with the number they just randomly dialled, they'll be stumped.