Similar look and feel of WhatsApp and other commonly used messaging apps, makes switching easy. Signal requires your phone number as an personal identifier.
Reviewed by Gabriel Bachmann
Signal
signal.org 4.7 (7)
Rate Signal: No account needed
Threat level
Covered
A covered pick. Anyone can use it as a private drop-in, with no setup or know-how. Enough for most people. Threat levels
Our take
The phone number requirement is the real friction, and there is no getting around it without a burner. Accept that and Signal is the easiest secure messenger to actually get your non-technical friends onto, which matters more than any feature, because the most private app is useless if nobody you know will install it. The desktop apps are good and the protocol is the one everyone else copies.
GitHub at a glance
signalapp/Signal-Android
Stars
29,038
+ 146 this week
Last commit
13d ago
healthy
License
AGPL-3.0
Latest release
v8.17.3
15d ago
Stars, last 35d
Website at a glance
signal.org
D score 35
Weak website security headers
Graded by Mozilla HTTP Observatory, tested 1d ago
Inspect this site yourself
Measures the security configuration of the tool's own website, not the privacy of the product itself. A strong tool can still score low here.
Signal alternatives
Delta Chat Delta Chat doesn't have their own servers but uses the most massive and diverse open messaging system ever: the existing e-mail server network. Chat with anyone if you know…
Brave Talk The person creating the call requires to use Brave Browser, but the participants can join from any browser.
Jitsi Meet Desktop version downloads can be found here .
Stoat Open source, self-hostable Discord alternative, formerly Revolt. Built for communities that want off Discord, but it is not end-to-end encrypted.
iMessage Apple's built-in messenger. End-to-end encrypted between Apple devices.
Threema No native desktop apps available yet, but there is a web version for your browser. No phone number is required to signup but there is a payment involved to get the app.…
Signal license, in plain English
AGPL-3.0 Strong copyleft · network
Free to use, even commercially. Changes must be published under the same license, and running a modified version as a network service counts as distributing it.
Permits
- Commercial use
- Modification
- Distribution
- Patent use
- Private use
Requires
- Disclose source
- Network use is distribution
- Same license
- State changes
- License and copyright notice
Does not provide
- Liability cover
- Warranty
Why it matters: The network clause is the point. Anyone who runs a modified version as a hosted service has to publish those changes, so the code handling your data stays inspectable. This is why privacy-first projects reach for AGPL.
Plain-language summary of the project's license, not legal advice. Read the full text for the exact terms.