Threema is described as 'New mobile messaging app that puts security first. With true end-to-end encryption, you can rest assured that only you and the intended recipient can read your messages' and is a very popular instant messenger in the security & privacy category. There are more than 100 alternatives to Threema for a variety of platforms, including Android, iPhone, Windows, Mac and Linux apps. The best Threema alternative is Signal, which is both free and Open Source. Other great apps like Threema are Telegram, Element, Tox and WhatsApp.
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 free.
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.
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.
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.
Open-source messaging platform enabling private, identifier-free chats, encrypted group discussions, file and media sharing, plus audio and video calls. Employs double-ratchet protocol, stores user data on-device, protects metadata, and lets users self-host relay servers.
Secure communication platform featuring encrypted chats and calls, file and media sharing, self-deleting messages, device verification, group collaboration, and customizable settings. Supports use across multiple devices with no phone number required for access.
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.
Decentralized messaging app enabling secure peer-to-peer communication over Bluetooth mesh networks with end-to-end encryption, channel-based group chats, store & forward delivery, automatic peer discovery, no accounts or phone numbers, and privacy safeguards.
An open-source decentralized and encrypted messaging app even without internet connection via Wi-Fi and Bluetooth. Messages are stored securely on your device, not in the cloud. Connect directly with nearby contacts - no Internet access is required.
Threaded group conversations combine live and asynchronous messaging, separating topics for organized collaboration, supporting open-source, cloud, and self-hosted deployments, secure communication with encryption, and multi-platform access for diverse teams.
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Independent and good cryptography.