The Doctor chuckled a bit at that. After slipping on his thick framed glasses he pulled that PDA out of his pocket and turned the sonic screwdriver to it. He quickly scrolled through the various faces that popped up on the screen pausing to blink for a moment at some of them, wondering how they could be there. Especially one in particular. But then he moved on, thinking that it was quite possible it was just... some lookalikes or something of the sort.
"Oh, ye of little faith," he said simply, grinning, eyes not leaving the little screen. "You've never been in a TARDIS."