Thomas Clayton, CEO of Bubble Motion, with its product, Bubbly—think a mobile device-focused Twitter using audio instead of script. His current project is his sixth startup.. Others he’s built include an automobile restoration business he started in high school and sold for $900,000; an online DVD business he started in college; and a high-end audio manufacturer that sold speakers for $80,000 a pop and used authentic Ferrari red paint. Bubble Motion went from 0 users to about 16 million in two years and is working on a push into the Americas.

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