Setting the scene
Car phones existed, but Motorola executive Martin Cooper wanted a truly handheld cellular device to prove his team could beat rival AT&T in the race for mobile telephony.
What happened
Cooper placed the first public handheld cellular call on April 3, 1973, in New York City, dialing Joel Engel at rival Bell Labs on a prototype DynaTAC phone that weighed over two pounds.
Why it still matters
Cellular networks took another decade to commercialize, but that sidewalk call proved mobile phones would leave the car dashboard. Memorable detail: Cooper made the call while standing on Sixth Avenue, not from inside a lab.
Background
Mobile phones later shrank from briefcases to pockets.