RadicallyOpenSecurity performed an external crystal-box security audit of the GNU Taler iOS wallet (excluding wallet-core) funded by NGI. You can find the final report here. We already addressed all significant findings except enabling FaceID/TouchID to enable using the app which remains a feature on our roadmap to be addressed in the next few months. We thank RadicallyOpenSecurity for their work and the European Commission's Horizion 2020 NGI initiative for funding the development of the iOS wallet including the security review.