The mobile-banking Trojan family, Trojan-Banker.AndroidOS.Gugi is interesting due to its use of the WebSocket protocol to interact with its command-and-control servers. This protocol combines the advantages of HTTP with those of commonly used sockets: there is no need to open extra ports on a device, as all the communication goes through standard port 80. At the same time, real-time data exchange is possible.
It is worth noting that even though this technology is user-friendly, it is not that popular among attackers. Among all the mobile Trojans that utilize WebSocket technology, more than 90% are related to the Gugi family.