Voice and video
Start a supported call from the channel’s call controls.
Encrypted calls
Make voice and video calls inside supported City of Hats channels. Talk through your Hat identity while keeping the conversation separate from your carrier number.
No phone number or email required for core Hat use.

The useful difference
Start a supported call from the channel’s call controls.
Connect with a Hat identity rather than exchanging personal phone numbers.
Use the available calling experience on your supported browser, iOS or Android client.
How it works
Confirm you are calling the intended contact.
Use the call control and grant microphone or camera permission only when needed.
Use a suitable network and a supported client; call behavior can vary by device and version.
Know the boundary
The documented Hat call encryption boundary does not protect an unlocked endpoint, a recipient recording the call or all connection metadata. Carrier SMS and telephone calls are a separate mode and are not end-to-end encrypted Hat calls.
Review the security evidenceQuestions, answered
Open City of Hats to review the controls available for your client, content and plan. The app shows applicable requirements before you proceed.
Verify the recipient, use a supported device and choose appropriate access and retention rules. Review the Security Evidence Center for boundaries and evidence status.
City of Hats is free to use. Feature availability and limits vary by plan and client. Premium is optional; review current limits in the app or on the plans page.
Explore what matters next
Start with a Hat
Start free. Choose your controls as the work requires them.