What's common between WhatsApp & Viber co-founder?

Bollywood strikes again. WhatsApp co-founder Jan Koum and Viber co-founder Talmon Marco are slugging it out in the messaging app arena, but what do the two have in common? A love of Hindi movies.

In February, 38-year-old Koum confessed to ET at the Mobile World Congress in Barcelona that as a kid, he couldn't get enough of Mithunda. "I grew up watching Indian movies in Russia. I am quite familiar with Bollywood. I watched Disco Dancer some 20 times as a kid."

Meanwhile, it's the 'All izz well' anthem for Israeli-American Marco, who grew up in Tel Aviv. Currently based in London, the 41-year-old recently told ET that he's a huge fan of 3 Idiots. All the world is a stage, Bollywood?.