I am searching for either a camera app with hardware button support, or for some other solution that would make it possible to use hardware buttons for making photo (shutter) in a camera app.
My phone, Samsung Galaxy S III mini doesn't have separate camera button, only power button, home button, back and menu buttons, and volume rocker. It is IMHO much easier to use hardware button than to try to hit software button on camera screen.
I think this should be possible, because built-in Phone Call app can be configured to accept call with Home button, and end / cancel the call with Power button.
This question can be considered to be continuation of How to assign a hardware button to camera which is about using hardware button (e.g. Home) to start camera.