Warner Bros.

So, for example (I'm literally making this up), Vodafone could strike a deal with WhatsApp by which WhatsApp will work faster on Vodafone than any other messaging app runs on Vodafone.

Vodafone can then tell customers: if you want to use a different messaging service (let's say Viber) at a high speed like WhatsApp, you have to pay extra money. This basically allows Vodafone to bring WhatsApp more customers than Viber, and to effectively destroy the hopes of any 19-year-old in Andheri who was on the verge of inventing the coolest messaging app ever (why would you pay for his new app when you get WhatsApp for free?). It allows telecom companies to influence the success and failure of upcoming apps and services.