Secure Messengers in 2025: From Protocols to Apps

In the search for truly secure communication, it's easy to get lost in marketing promises. However, real privacy doesn't start with picking a popular app, but with understanding the technologies behind it. Open and decentralized protocols offer the most control over your conversations.

That's why we'll start with the most fundamental approach: the open protocols Matrix and XMPP (Jabber). Then, we'll cover other excellent, but simpler-to-use messengers for those looking for strong, out-of-the-box protection.

Option 1: Open Protocols for Maximum Control

This is the choice for those who don't want to depend on a single company or application. By using an open protocol, you get the freedom to choose your client (app) and server, and even run your own. It’s similar to email: it doesn't matter which provider you use, you can still write to anyone.

Matrix: The Modern, Universal Standard

Matrix is a modern, open protocol for decentralized and encrypted communications. Its strength lies in its versatility: it supports not only chats but also audio/video calls and "bridges" to other networks (like Telegram, Discord, etc.), allowing you to unify all your communication in one place.

How it works: You register an account on any public Matrix server (like matrix.org) or run your own, and then you log in to your account through any client application.

  • Recommended Client: Element
    Element is the flagship and most popular client for the Matrix network. It's available on all platforms and is user-friendly, making it the best starting point.

XMPP (Jabber): The Time-Tested, Flexible Standard

XMPP (often known by its old name, Jabber) is a veteran among protocols, a true example of reliability and flexibility. It's federated like Matrix and offers a huge selection of clients to suit any taste. For robust encryption, the OMEMO technology is used today.

How it works: You find a public XMPP server that supports modern features (like OMEMO), register an account (a JID, or Jabber ID), and connect using your client of choice.

  • Recommended Clients for Different OS:
    • Android: Conversations
      Considered the gold standard for XMPP on mobile devices. It has an excellent interface and the best out-of-the-box OMEMO support. It's a paid client, but well worth the price. (Website)
    • Desktop (Windows, macOS, Linux): Gajim
      A powerful and feature-rich client with plugin support that enables OMEMO and other modern features. It's ideal for desktop use. (Website)
    • iOS: Monal or Siskin IM
      Good, modern options for Apple users that are actively developed and support OMEMO encryption.

Option 2: Simple and Reliable Apps

If setting up a client and choosing a server seems too complex, there are excellent standalone applications that offer a high level of privacy without the extra steps. They are generally centralized but are managed by organizations with a good reputation in the privacy space.

Signal: The Industry Standard

Signal is widely regarded as the benchmark for private messaging. Developed by a non-profit foundation, it uses a best-in-class encryption protocol that has become the standard for the entire industry. Pros: E2EE by default, minimal metadata collection, open source. Con: Requires a phone number for registration.

Threema: Anonymity from Switzerland

Threema is a paid, open-source messenger built from the ground up for maximum confidentiality. Pros: No phone number required (full anonymity), based in Switzerland with its strong privacy laws. Cons: It's a paid app and has a smaller user base.

Session: Decentralization and Anti-Surveillance

Session uses a decentralized network to route messages, hiding your IP address and protecting your metadata. Pros: No phone number required, censorship-resistant. Con: Message delivery can be slower due to its complex routing.

A Word on WhatsApp and Telegram

So, why aren't the two most popular "secure" apps recommended?

  • WhatsApp: While it uses Signal's encryption, it is owned by Meta (Facebook). Its business model is data collection. It gathers a vast amount of metadata about you, your contacts, and your behavior.
  • Telegram: Its marketing is misleading. End-to-end encryption is not enabled by default. It only works if you manually start a "Secret Chat," which is not available for groups. All your regular chats are stored on Telegram's servers.

How to Make the Right Choice

Choosing a secure messenger is often a trade-off between the level of control and ease of use. For maximum control over your communication and independence from any single company, it's worth looking into open protocols like Matrix and XMPP. If you prefer a simple yet extremely reliable out-of-the-box solution, Signal, Threema, or Session will be an excellent choice.

The key is to make an informed choice, understanding the strengths and weaknesses of each tool. This is the foundation of a sensible approach to your digital privacy.