Valerie Wagoner, 

The Bangalore-based startup tripled its revenues and customer base, and expanded into Sri Lanka, Bangladesh, the Philippines, and South Africa. Then, in January, Twitter acquired it in a big-bang deal, said to be between $30 million and $40 million—the microblogging platform’s first buyout in India. “From day one, we wanted to be a global company. With this, we will get there faster,” says Wagoner, who likes to call herself an “emerging markets entrepreneur”. ZipDial’s USP—using missed calls as a marketing tool—speaks to that.