Progress
I was able to implement the bluetooth function between a mobile app and the Arduino unit. The app currently can switch on and off the Arduino’s LED and show temperature data taken from the Arduino all through bluetooth.
I tried to connect the battery with the Adafruit battery backpack, but some smoke came out. Turns out the battery’s wire port is not compatible with Adafruit’s receiving port because the polarities are reversed – Adafruit sets their positive on the right side while the negative is on the left, the battery is the opposite. Although the Adafruit circuit appears fine, there is a possibility that the chip did blow. I considered taking out the wires form the batterie’s port to switch the contacts, but then I was informed that I can accidentally short-circuit the battery with the contacts out if they somehow touch each other.
Next Steps
I will be trying to connect the OLED screen to the Arduino. After, I will try to display the temperature on it to ensure the connection across app, Arduino, and screen is seamless. The next step would be to try and display any text on the OLED, first directly from the Arduino with its uploaded sketch, and then from the app with the Arduino as the medium. I want to work on how a user can type in a textbox on the app and immediately have that shown real-time on the screen.
I will also have to be purchasing a new Adafruit backpack and their lips battery because none of the third-party batteries I could find on Amazon are oriented in Adafruit’s polarity.