Installing ODK Collect in File Locker app

1. What is the issue? Please be detailed.
I am trying to secure ODK Collect on the cellphone by moving or copying it into File Locker app. How do i do that on the phone?

2. What steps can we take to reproduce this issue?
None

3. What have you tried to fix the issue?
Drag and drop into the File Locker folder.

4. Upload any forms or screenshots you can share publicly below.