I’m trying to create a small device (keychain) size with different LED lights on it that communicates via Bluetooth to a phone and receives a signal from an app — the app would change LED colors based on input from another user on another device.
1. Keychain 1 button is pressed
2. Keychain 1 sends that signal via Bluetooth to cell phone 1
3. Signal processed by app on cell 1
4. Signal sent via internet to app on cell 2
5. Signal received by app on cell 2
6. Cell 2 sends signal to keychain 2 via Bluetooth
7. Keychain 2 LED changes color correspondingly
Basically if user 1 changes their button to RED on their keychain, the same button on keychain 2 turns RED; user 2 hits and changes their button to BLUE; same button on user 1 correspondingly changes to BLUE.
Each user would have an assigned color so it isn’t a free choice. If I hit a button, my prescribed color illuminates on all devices in that group.
I’m looking for help in how to do this.
Best if someone would be versed in both hardware and software for prototyping this.