The following video is from Friday's installment of The Motley Fool's Weekly Tech Review, in which host Chris Hill and analysts Eric Bleeker and Jason Moser look at the biggest stories driving the tech sector this week.

Snapchat, an app-based service that allows users to send photos and other content to friends or groups, which is only visible to the recipient for a variable length of time before vanishing permanently, has been valued at an unbelievable $800 million in its most recent round of fundraising. In this segment, Jason and Eric discuss why this valuation seems a bit frothy, why the concept might prove difficult to monetize, and why user engagement of this and other services considered to be potential Facebook (META -11.32%) disruptors may not be eating into Facebook's engagement level nearly as much as analysts fear.

The full video is available here .

The relevant video segment can be found between 3:55 and 7:58.