An open-source messaging app emphasizing privacy with encrypted communication. Share texts, calls, photos, and videos without ads or trackers, available across major platforms. Developed by Signal Technology Foundation and praised globally for security measures.

Maximize your messaging experience with efficient communication, speedy delivery, and optional end-to-end encrypted Secret Chats. Engage in unlimited channels and groups up to 200,000 members. Enhance chat management and media sharing with Telegram Premium and its exclusive benefits. All core features remain...

Provides secure collaboration with end-to-end encryption, supporting chat, voice, and video calls. Available on all major platforms, it enables digital sovereignty with a decentralized design and interoperability through bridges to systems like Slack and Teams. Includes enterprise-grade SaaS.

An integrated platform for text and voice communications. Offers tailored channels for different topics, customizable moderation tools, low latency for fluency, and managed user roles for optimal community facilitation.

Matrix defines a set of open APIs for decentralised communication, suitable for securely publishing, persisting and subscribing to data over a global open federation of servers with no single point of control.

Pidgin is a chat program which lets you log into accounts on multiple chat networks simultaneously. This means that you can be chatting with friends on XMPP and sitting in an IRC channel at the same time.

With the rise of widespread government monitoring programs, Tox is an easy to use application that allows you to connect with friends and loved ones without anyone else listening in.

Go ahead, video chat with the whole team. In fact, invite everyone you know. Jitsi Meet is a fully encrypted, 100% open source video conferencing solution that you can use all day, every day, for free.

Exchange messages without SMS fees using this app for iPhone, Android and desktop, featuring group chats, multimedia sharing, and video calls. The app requires an internet connection and the latest version for optimal functionality.

Offers unified communication for teams with advanced real-time messaging, contextual features, versatile chat tools, and organized conversations in dedicated channels with integrated file sharing on Mac, Windows, Linux, and mobile platforms for enhanced productivity.

Mumble was the first and is the most successful and wide spread free and open source software for VoIP. It was the first VoIP software to provide low-latency audio suitable for gaming, and at the same time was a pioneer in high audio quality.

Jami (formerly GNU Ring, SFLphone) positions itself as a potential free Skype replacement