Weekly poll: face scanning vs. fingerprint readers

Even old sleuths like Sherlock Holmes know that a fingerprint can identify a person. Today, fingerprints are read multiple times a day - it's routine - thanks to the readers on modern smartphones. But is that the best way for a device to know that it's being handled by its rightful owner? What about 3D face scanning? "Wanted" posters have been used for even longer than fingerprints and they work because your face is unique. Well, most of the time, unless you have a twin or a sibling or a kid that looks like you. Capacitive fingerprint readers are fairly simple devices, readily available...