Automated App Signing

Overview

In my role as central app manager at Siemens, correct and timely signing of iOS and Android applications was a central requirement. Expired or incorrectly signed apps cause distribution failures on managed endpoints. I designed and built a standalone tool to automate and safeguard this process.

Initial development was completed in September 2017. The program was then continuously operated and improved. From October 2024, team members took over full ownership of operations and development, freeing me to focus on new areas.

Features

Validation and re-signing

The tool analyses incoming app packages (IPA for iOS, APK/AAB for Android), validates certificates and provisioning profiles, and automatically re-signs packages where necessary, including unpacking, modifying, and recompiling the app bundles.

Developer collaboration

When package errors or missing metadata were detected, a semi-automatic process was established that directly involved the responsible developers in the ongoing development of the tool. Feedback from the app store platform and development teams fed continuously into the tool, addressing recurring issues at their root. Coordinating between development teams and distribution infrastructure, as well as driving the tool’s development, was my responsibility.

Operations and handover

I developed and operated the program in its entirety. Team members were progressively brought up to speed and by October 2024 were fully able to maintain and extend it independently.