The notion of a completely secure online messenger is a myth. Without a deep technical understanding of how these systems operate, users cannot guarantee the privacy of their conversations. Access to private messages is ultimately a matter of time and money. State actors, possessing vast financial resources and undisclosed capabilities, hold significantly more power than any individual. Governments actively work to lower the cost of accessing citizen data and may even covertly finance popular messaging applications to create an illusion of security. Consequently, the primary function of encryption keys is often not to prevent access entirely, but to keep rival states out.
Access to private information is frequently resolved through non-technical means. If the value of your data is high enough, human factors such as betrayal become a viable attack vector. Installing an application does not inherently provide security; rather, it expands your attack surface. True security requires evaluating a multitude of factors before adopting any platform.
Claims of absolute security from messengers that require phone number registration, such as Signal or Telegram, are fundamentally flawed. A phone number directly identifies the user and their location, regardless of how the SIM card was acquired. Additionally, relying on mainstream operating systems like Windows or Android while expecting robust anonymity is unrealistic, as these platforms are not designed with privacy as their primary objective.
A truly protected messenger can only increase the cost of accessing your messages, thereby limiting access to higher levels of adversaries. If your private life holds no significant interest to powerful entities, standard applications may suffice. However, high-profile individuals must consult trusted IT professionals, and those at the highest levels of power should avoid mobile devices and messengers entirely. Ultimately, there are no secure messengers—only the price of accessing your messages, which you must strive to raise.