README.me correctly states
This method uses the screenshot function of the device. It's exactly the same as pressing the Home+Power button or whichever key combination is used for screenshots on that phone.
Issue
Update
Issue 1: The app
The native method to take screenshots simulates a press of Home+Power button and uses the screenshot method of your device.
It should be modified to:
The native method to take screenshots simulates a press of Home+Power button or whichever key combination is used for screenshots on that phone and uses the screenshot method of your device.
Issue 2: Accessibility settings
The accessibility settings for Screenshot Tile says:
If this service is enabled, the app can simulate a power+home button press to take screenshots.
It should be modified to:
If this service is enabled, the app can simulate a power+home button press or whichever key combination is used for screenshots on that phone to take screenshots.