Edit: Someone told me the apps are region locked
APK download - CovPass (17.1 MB)
APK download - CovPassCheck (16 MB)
APK rehosted directly from the Google Play Store
Edit2: Some have issues with name formatting being wrong/cut off
Edit3: Cut off names is an issue with Taiwanese certificates and not the apps.
This official German app can store the digital certificate. Has English language.
https://www.digitaler-impfnachweis-app.de/en
There is also an app to check validity of digital certificates of others (e.g. for establishments)
https://www.digitaler-impfnachweis-app.de/en/covpasscheck-app/
edit: removed old share links