Your phone could become a tool for detecting lies

So in other words: useless.

> However, it has its limits and shouldn't be used in courtrooms or other high-stakes environments, he said.

Good thinking. Anxious people (innocent people are often anxious, I'd say) would most likely fail at the test.

Come on, you can't detect lies based on physiological indices such as blood pressure, pulse, respiration, and skin conductivity. Those are unreliable, and not proof or evidence of anything.

"Polygraphs measure arousal, which can be affected by anxiety, anxiety disorders such as posttraumatic stress disorder (PTSD), nervousness, fear, confusion, hypoglycemia, psychosis, depression, substance induced states (nicotine, stimulants), substance withdrawal state (alcohol withdrawal) or other emotions; polygraphs do not measure "lies". A polygraph cannot differentiate anxiety caused by dishonesty and anxiety caused by something else."