Telegram Messenger: Features, Security, and Controversy

launched in 2013 by brothers Nikolai and Pavel Durov, Telegram operates as a free, cloud-based messaging platform accessible across all major operating systems, including iOS, Android, Windows, macOS, and Linux, as well as via the web. The service facilitates the exchange of messages, photos, and videos, supports group creation and channels, and offers voice and video calling capabilities. Telegram employs robust technology to secure messages during transit, a process known as “transport encryption.” However, end-to-end encryption, where only the sender and receiver can access messages, is exclusively available in its “secret chats” feature. Within these secret chats, users can also configure messages to self-destruct after a set period. Standard chats and groups, conversely, are not end-to-end encrypted and are stored on Telegram’s servers, which, while convenient for users switching devices, raises data protection concerns. Telegram retains metadata,such as IP addresses,device information,contacts,and group memberships,for up to 12 months,potentially for spam analysis or disclosure to authorities upon request. Key advantages of Telegram include rapid synchronization across devices, support for large groups and channels, integrated bots and mini-apps, the aforementioned secret chats, and two-factor authentication, all offered without advertising. Conversely, its disadvantages include the lack of automatic end-to-end encryption for standard chats, the retention of metadata, and criticism from security experts regarding its proprietary encryption methods. The platform has also faced scrutiny for its alleged misuse by extremist groups. Recent developments indicate a shift in Telegram’s data disclosure practices; following Pavel Durov’s arrest in France, the company has reportedly increased its transparency with authorities, with inquiries processed in Q1 2025 substantially exceeding those in the prior year. Furthermore, Telegram has encountered sanctions in several countries, including Australia and Spain, attributed to issues concerning extremist content and copyright infringements.