Quality Control: How We Do It - 30 point checklist

INSPECTIONS

Earpiece Audio is not distorted.
Front camera takes great selfies
Front camera Video recording is clear and ready for video chat
Accesses Wi-Fi
Connects to a cellular network
Serial Number is clear for activation with your carrier
Ring/Silent switch works
Volume buttons work
Authenticated Apple Product
Device is cleaned thoroughly
Rear camera captures true, sharp images
Autofocuses as expected
Video recording is smooth
LED flash is nice and brightSleep/Wake button works
SIM card tray works
Touchscreen functions fluidly 
Glass is free of damage
Blacklight is bright
No dead pixels
Home buttons operates smoothly
Headphone jack works
Microphone records clear sound
Voice commands work
Device charges normally
Device passes data via USB
Loudspeaker is ... loud