In the Code section, you've seen how to change the hotkeys, and learned the importance of real-world testing. There are a lot of potential improvements to this project that are worth exploring.

• Do you need to control a different application? Find the hotkeys, change the code, and try it out!
• The LEDs on the PyRuler currently light up when pressing the button. As we're toggling something, perhaps it would be better if the lights instead turned on/off with each button press?
• The buttons are capacitive sensors, and the symbols don't match the functions. Could you put some kind of covering over the buttons that still allow the touch sensors to work?
• Rather than using the touch sensors, you could always wire your own capacitive touch pads or switch. What kind of panic switch would you prefer?
• Can you design a better enclosure - maybe one that can be printed as a single piece?
• Could you use the Trinket M0 with a single big panic button and a rotary switch to change between applications?

If you make any improvements, or even just make your own version, I'd love to see it! You can always reach out to me @grajohnt on Twitter.