So, we need to decrypt the app before providing it to class-dump-z.
Follow the given steps to decrypt a signed iOS application:
You should have Clutch installed on your iDevice. You can install it from Cydia if you haven't done it yet. Once you enter the
clutchcommand in device shell, it will show you all encrypted applications available on iDevice:
Now, select the app that you want to decrypt and provide a name to clutch; it will decrypt the app and show the location where it's been decrypted:
Once the application is decrypted, you can use class-dump-z. Provide a decrypted IPA file...