WhatsApp Guy $19 Billion Upgrade ... In Arm Candy?

2/25/2014 11:00 AM PST

WhatsApp Co-Founder Jan Koum -- $19 Billion Upgrade ... in Arm Candy?

This is WhatsApp co-founder Jan Koum in Spain with his girlfriend ... celebrating Facebook's $19 BILLION purchase of his company, and his 38th birthday.

So, the obvious question: when BILLIONAIRE Jan turns 39 ... will the same GF be in the picture?