Session encrypts your messages using the Session Protocol, an end-to-end encryption protocol built on libsodium, a highly-audited and widely trusted cryptographic library. We moved away from the Signal protocol so that we could built the standard for decentralised encrypted messaging apps — learn more about that here.
A technical description of the Session Protocol can be found in our technical deep-dive blog.
You can also refer to our technical whitepaper for further details.