Below I have posted a simple program I made.
I want the app to display a big "Warning" message (with sound if it's not too difficult) when it receives a 0 (zero) from the bluetooth on the Arduino.
I am not good with programming so apologies for the simple questions.
This worked, even though I don't understand any of it.
I finally got the message I wanted. Now I just need to find out how to add a sound and maybe open a new screen when the message is received. Thanks a bunch!