Unlock phone with your face without downloading any app system secret

Hi guys good evening aaj me apko Android phone ke ek anokhe feature se ru aru karaane waala hun ji haan android ka vo feature jiski madad se aap apne phone ko apne face se unlock kar sakte wo bhi bina kisi app ko download kiye jii haan par iske Liye apke phone ka system 5.1 ya usse uper ka hone chahiye to chaliye jaante hain ki ise kaise setup karna hai iske liye aap apne phone ke setting me jaeye or wahan se security me click kijiye or wahan smart lock ye likhaaya hoga us par tap kijiye ab wah apse apne phone ko apne face ke saamne laane ko kahega yaad rakhiye ye low light me hi effective rahega jyada light hone me use phone unlock karne me thodi pareshani ho sakti hai ab poora setup karne ke baad aap apne phone ko apne face ke saamne laiye agar usne apke chehre ko read kar liya hoga to meeche lock ka theme badalkar dark ho jaega