Thanks! The tool has a built in certificate authority (CA) to generate TLS certificates. So to intercept TLS traffic from a phone, you export the CA's root certificate and import it onto your phone. If you're on PC, you can also launch a browser preconfigured to intercept traffic.

This is the standard pattern for these kinds of tools.

As it's not always a straightforward process for people who haven't done it before, there's instructions for a variety of platforms in the documentation: https://docs.pakikiproxy.com/#/getting_started/intercepting