Swimlanes.io is a free webapp for making sequence diagrams. You simply edit the text on the left and the diagram is updated in real time. You can download your sequence diagrams as images or distribute with a link.
title: Scenario 1 Mobile/Web App -> Bank Server: Send CMND + selfie to Bank server Bank Server -> Bank Server: Internal bank's processing Bank Server -> TrustingSocial Server: Call eKYC services as OCR, Face Matching, Liveness, Tampering,.. Bank Server <- TrustingSocial Server: Return eKYC result. Bank Server -> Bank Server: Internal bank's processing eKYC result Bank Server -> Mobile/Web App: Return result to Mobile/Web App