Current problem
It is effectively impossible to use call controls if you use a screen reader because even if you know how to bring up the call controls by selecting the (unlabeled) profile button in the center of the call screen, the controls disappear before they can be read and the a control can be selected.
Proposed change
Add an accessibility setting to never automatically hide any app controls, so that blind users and users requiring a screen reader might be able to operate these controls.
Platform
Android, iOS
Additional information
Reproduction steps
On the mobile app:
1) Enable your devices screen reader.
2) If you can normally see: close your eyes.
3) Try to use any of the call controls.
The knowledge that this is the reason why the call controls can't be used is only available to me because I am sighted.