I just can't take seriously any VC valuing this company at $10 billion, and I'd be furious about this if I had money invested with any of the firms involved. According to Forbes[1] they have 100 million users. That seems high, but even if that's the case...since when is an app worth $100/user? Even Whatsapp didn't get that on a per-user basis.
[1] http://www.forbes.com/sites/parmyolson/2014/08/26/report-sna...