SpardaSecureApp (v.2.1.0.2) doesn't allow to register account [answered]
Recently I installed SpardaSecureApp version 2.1.0.2 on my XA2 and wanted to assign it to my Sparda bank account. There's a scan mode that doesn't seem to work as with many other banking apps using photo TAN. The manual way always crashed my phone.
Eventually I found a rather old version in my backup, installed that and the dialogue worked, however Sparda told me that this version was too old. On the site Android APK I found a list of more recent previous versions. So I installed version 2.0.3.0. It looked pretty much the same but the manual registration dialogue worked with that version. Once again, Sparda told me to upgrade to most recent version. I did so with Aurora Store and finally registration also works with the latest version.
Hopefully this is helpful for other customers of Sparda bank.