Threema – The Secure Messenger

Threema – The Secure Messenger Threema is a secure, paid end-to-end encrypted messenger for Android, offering private chats, encrypted calls, and video calls. Get a random Threema ID without sharing personal info.

Threema – Secure Messenger

Threema is a paid, proprietary instant messaging app built around end-to-end encryption. It lets you exchange messages and also supports secure phone calls and video calls. Even while data is traveling, it remains encrypted—helping protect your conversations from hackers, companies, and government interference.

Each person gets a random Threema ID automatically, without needing to share personal details or create an account. One reason the app is known for strong security is that Threema GmbH is headquartered in Switzerland, and it follows European privacy requirements such as the GDPR.

Pricing: $4.99. Languages include English, Basque, Czech, Dutch, French, German, Italian, Japanese, Simplified Chinese, and more. Compatibility includes Android 4.0+, iOS 6.0+, and Windows Phone 8+.

Key Features

Encryption

Threema uses continuous end-to-end (E2E) encryption and keeps the amount of unencrypted data sent to corporate servers as low as possible. Anything that appears on the company’s servers is only there briefly. Once a message is delivered, the message content—along with related metadata—is removed from the server.

Private Message Protection

You can lock down sensitive chats and keep them hidden from your Threema home screen chat list. Private chat notifications also avoid showing message previews.

To enable this:

• Press and hold the conversation you want to protect.
• Select Mark as private.
• Create a PIN.
• Enter the PIN whenever you want that private chat to appear.

Data Storage and Removal

Threema keeps your information on the devices involved in the communication. The system doesn’t require storing large amounts of metadata on its servers to deliver messages. When needed metadata is used for delivery, it’s removed afterward.

Data stored on your device is secured with AES-256 encryption, including media files you send through the Threema network.

Media Library

The in-app media library supports image recognition, letting you search for photos using keywords. This reduces the need to manually scroll through large numbers of images on your device.

Because recognition runs locally, the image doesn’t leave your phone. If you prefer not to use this capability, you can simply disable it.

Search

Use global search to look through all of your chats at once, instead of searching one conversation at a time.

Threema Web

Threema.Web is a browser-based interface that works alongside a Threema-enabled mobile phone. You link it to a specific device that already has the Threema app installed. It is not a separate product and doesn’t come with its own Threema ID—its purpose is to let you control and chat through your phone using a desktop browser.

User Tips

• Use end-to-end encryption: If you’re using Threema Work, rely on its E2E encryption so sensitive team communication stays protected.
• Fine-tune notifications: Configure alerts so you only receive them during working hours, helping you focus.
• Collaborate more effectively: Create group chats, share files and media, and use tools like text formatting and polls to improve team communication.

Pros and Cons

Pros

• One payment, continued use



• Use Threema anonymously
• No user data collection
• No ads



• No phone number required
• Simple, easy-to-use interface
• Allows backup via a third-party server
• Strong group chat tools: smart replies, polls, and sharing videos, pictures, locations, and files
• Chat from a desktop using Threema Web
• Contact synchronization

Cons

• Works only with certain versions of Android, iOS, and Windows
• Not free
• Smaller user base compared to some alternatives



• No support for two-factor authentication