Units sold: 250 million

The 1100 may look positively archaic by today's standards, but indeed, in a twist of irony, its primitive features may have been its biggest draw. At a time when cell phones began offering colour screens and cameras, the stripped-down Nokia was the perfect unit for budget users, especially those in developing or underdeveloped countries. Since its launch in late 2003, 250 million Nokia 1100s have been sold, easily making it the world's most popular cell phone of all time.

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