With Qustodio Premium, you can read the content of private messages (SMS text) received or sent on Android devices. Qustodio offers the option to know when text messages/SMS were sent or received and to whom, as well as the ability to read the messages exchanged. Please refer to this article to read more about SMS monitoring with Qustodio (Android only).
All other social networks or apps, such as Facebook, Skype, Instagram, Snapchat, TikTok, WhatsApp, 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.