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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KUMA 
ClockLink 
freetinyimages 
木曽町田中屋豆腐 
水琴晶子（みことあきこ） 
PSPCF 
カワシマヒロキ（ひーさん） 
bokushi 
さち 
田仲なお美 
佐藤淳一（朝活習慣化キャリアコーチ）