Keywords: free, team, communication, messaging, chat, end-to-end, encryption, file, transfer, social collaboration, group, mobile, desktop, secure, privacy, crypto

Sid is an End-to-end secure teamwork tool to make your team communication safer, simpler and more efficient. Connect with your team members and keep everyone on the same page.

Fast communication - one-to-one or within groups

Set up your team easily and start right away with secure messaging and file transfer. Use it for private and team communication. Team contacts are exchanged with every new team member automatically.

Sid comes with structured communication in dedicated channels: Organize your team conversation and customize it to match your personal needs.


Available for mobile and desktop devices

Sid clients are available for desktop computers, laptops and as native apps for iOS and Android. You can use it on any operating system like your computer in the office or on your smartphone anywhere else. Whatever you do on one device is reflected on all other devices, so everything is kept in sync.


Security by design

Sid uses end-to-end encryption for every message and file transferred. The encryption keys are generated and stored on your devices only. Unlike other password driven systems, your private key is used for authorization and authentification.

When working with Sid, your data is safe and no third-parties can decipher the data while being transferred. No one will be able to read your messages or decrypt your files.

We only support clients that run on your device natively to ensure maximum security.


Peer-to-peer and local file transfer

Sid is using a decentralized peer-to-peer technology to transfer data without uploading to a server or cloud. Your data is routed the fastest possibe way without taking detours and will use the local network if applicable. Exchange files of any kind and size with individuals, teams and external contacts.