JFYI: iOS does not use openssl (however an app might choose to use it). I believe it uses a FIPS compliant custom TLS implementation in Security.framework. I believe ssl pinning is circumvented on iOS by leveraging the objective-c runtime to hook the callbacks that an app would use to inspect the remote peer certificate. More info: https://www.guardsquare.com/en/blog/iOS-SSL-certificate-pinn...