To know quickly which one iPhone 4 and which one iPhone 4S from outside physically, visually :
Look at iPhone from upside
See the figure below :
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| Easy way to know iPhone 4 or 4S |
Between iPhone 4 and 4S look like the same, somewhat difficult to distinguish each other visually from the outside physically.
To know quickly which one iPhone 4 and which one iPhone 4S from outside physically, visually :
Look at iPhone from upside
See the figure below :
You can see the difference position of line/stripe of each iPhone.
To know quickly which one iPhone 4 and which one iPhone 4S from outside physically, visually :
Look at iPhone from upside
See the figure below :
