With Qustodio Premium, you can read the content of private messages received or sent. Qustodio offers the option to know when text messages/SMS were sent or received and to whom, as well as the ability to block all incoming messages, and to read the messages exchanged. Please refer to this article to read more about SMS monitoring with Qustodio.
The Advanced Social Monitoring option can track when a monitored user writes on Twitter, Yahoo Messenger, chats on Facebook and with whom, but it is not possible to read the actual conversation. To activate this option, please visit your Family Portal and go to Rules > Social Monitoring.
All other social networks or apps, such as Skype, Instagram, Kik, etc. can be monitored with Qustodio as any other application. However, Qustodio will not reveal what was said or exchanged between users on these apps or networks, only when the app was used and for how long. It is possible to completely block these apps, or set a time limit for each in Rules > Games&Apps.