Jan Koum , the founder of WhatsApp, has been quietly supporting Jewish relief efforts for refugees from Ukraine and other Jewish causes, reports JTA . Jan Koum, a Jewish immigrant from the Ukraine, was once reduced to relying on welfare. As a teen, his family lived on food stamps. He was born in Kyiv in 1976, Koum got his start in high tech working at Ernst & Young and later went over to work for Yahoo. He applied to work at Facebook in its early days, but was rejected. And then when the iPhones started rolling out he realized the...