Gqrx but with some changes which I really need.
Tested on Pi Zero 2W + 4.3" display.
Changes:
- moving the XAxis also by clicking on waterfall
- centering button on main screen (really needed on small screen)
- fullscreen button on main screen
- start DSP on startup
- XAxis zooming with wheel and left click
- SMeter removed
- TODO: pinch zoom on touch display
Works fine with FT450D and CAT control.