Inbuilt face scanner and fingerprint scanner both are available in this app for truth or lie detection. The app hears your audio as well while scanning.
Both the scanners are completely free even with voice detection also.
The app also speaks in robotic voice so your friends might believe that it actually works. Also, you can see when using the app that if you remove your face, the scanner stops and resumes only when you bring face back. But this app is actually a prank.
Though if you want to record the truth or lie detection, you can do it by unlocking that feature using in-app purchase. Which also allows you to share the video with any of your friends.
NOTE - PLEASE READ THE INSTRUCTIONS ON FIRST START CAREFULLY AS THEY WON'T APPEAR AGAIN DUE TO THE NATURE OF PRANK. MAINLY THAT IS PRESSING LEFT OF START DETECTION BUTTON WILL GIVE TRUTH AND PRESSING RIGHT WILL GIVE LIE.
DISCLAIMER- It has no relation to any real lie detector. Just meant to the extent of playing prank. Anything you do which is other than entertainment purpose will be at your own risk. We will not be liable for any loses or damages.