Breathing Trainer's support info
 Breathing Trainer is a simple app.
The only setting you can apply is changing the color mode of the app: light, dark or system.
Main screen of the app allows you to choose between different pre-programmed breating programs.
If you want to add a new one, click on customisation screen and add button (to remove added one - swipe left).
You need to provide a name of the program, specify how may phases you want and set each phase: decide if it needs to be inhale, exhale or hold and now long should it last.