David Lieb had the idea for Bump while daydreaming. He wrote the initial concept on a napkin, having no clue how it would change his life.
"In business school, one of the big things is meeting your classmates and networking," Lieb says, "and one day I just found myself typing in name after name after name, phone number after phone number, and I thought, 'Somebody should solve that problem.'"
With the help of his former coworker at Texas Instruments, Andy Huibers, Lieb created Bump, an app that allows people to transfer anything from photos to contact information from phone to phone just by bumping their devices together.
The app went live globally in March 2009. It took off quickly, getting a lot of coverage online and great reviews. Bump was even featured in an Apple commercial. Today, 4 years later, Bump has been downloaded over 130 million times around the world. It just goes to show you: trust your instincts and save your napkins.