My iPhone was locked on portrait position. To unlock the screen, you need to double click on iPhone home button (one button facing you just below the screen). When the icon appears at the bottom, swipe it right one. The icon on the very left of the list is the lock and unlock button. Clock it once to unlock and once again to lock.
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Tetsuro Watanabe 
SETSUKO 
さわ 
ClockLink 
錦糸町の天使 
落語好きプロコーチ 砂村よしお 
神谷保険 
bokushi 
Pacific Software Publishing, Inc. 
SanDiegoTown & LosAngelesTown 
内倉憲一