When Yo came up, analysts justified that part of the disbelief that the app arouses is due to the fact that it explores something that is not common in the United States, but makes a lot of sense in countries like India: missed calls. Facebook was one of those who paid attention to the phenomenon and started testing an advertising format that exploits this.
In India it is very common for a person to make a call and hang up before the recipient answers, which in Brazil is known as “ringing”. For each time this is done there is an explanation: inform that you have arrived, ask to return the call, etc.
That is why it is so used that some companies have adopted the missed call to offer products. Just touch a number and they return with recorded messages or SMS. this is what Facebook wants to explore.
The social network included a “missed call” button in some advertisements, so that users receive some kind of content related to advertising. It can be music, celebrity messages, game scores, among other things.
Advertising Facebook Online advertising