Ann: Market Update - Wangle Technologies, page-14

I am impressed by these numbers, if you try to understand the technology required behind it you should be too... We don't know the infrastructure requirements behind running something like this... For all we know they need juicy servers sitting behind some fat Internet pipes to be able to run there compression algorithms which pass on the data to the app/user.

I really doubt the App on the user device does all of that. This is why you cannot simply expect to scale it up to millions of users instantly. IT projects of this scale can get very complex to scale up.