Back when I had an iPhone 6s it wasn’t uncommon for me to drop the phone when trying to unlock it with TouchID, and I came to the conclusion that the sensor was placed too far down on the phone.
This made it unbalanced when trying to unlock it with out spreading your fingers out on the back of the phone to support it.
Having the fingerprint reader at the top of the device would mean less contortion of your fingers as it is close to where your thumb naturally rests.
It would be a similar motion to that of opening the iOS control center
Back when I had an iPhone 6s it wasn’t uncommon for me to drop the phone when trying to unlock it with TouchID, and I came to the conclusion that the sensor was placed too far down on the phone.
This made it unbalanced when trying to unlock it with out spreading your fingers out on the back of the phone to support it.
Having the fingerprint reader at the top of the device would mean less contortion of your fingers as it is close to where your thumb naturally rests.
It would be a similar motion to that of opening the iOS control center
Ah the person you were replying to though was talking about the in-screen fingerprint readers, which are generally higher up then the under screen