A feedback instance with option "Allow multiple submissions" does not show the values in moodle app which were previously entered on web.
The big problem here is, that values from optional items will be erased if not entered in the app.
If you use only the app or only the web all works as expected.

Steps to reproduce

1. As teacher in web
2. Create a new feedback activity instance.
3. Settings:
   1. Non anonymous
   2. Allow multiple submissions.
   3. The other options as default.
4. Create two or more optional questions.
5. As student in web
6. Complete all questions of the feedback and submit.
7. As student in app
8. Load the feedback again.
9. The values entered before are not shown.
10. Complete only one of the optional questions and submit.
11. On web: The previously entered values are completely gone.