for iphone 4,the proper case is a special iphone 4 case.there are many brands,such as cath kidston case,kate spade case,hello kitty case,TS-case and so forth.it all depends on your interest.
For business the proper case is a briefcase.
For travel, it's a suitcase.
For exhibits, a trophy case.
For beds, a pillow case.
For asylums, a nut case.
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