Brian Brushwood’s online career illustrates how regularly social apps go up in smoke. The magician, who spent 15 years touring college campuses, started to post video clips of his life on the road online in 2006. He amassed more than one million followers on six-second video app Vine and one million followers on Google+. Then, both shut down. 

“I am king of the failed platforms,” Brushwood, 48, said in an interview with The Information. “I have over 1 million followers on Twitter. We’ll see...”