I'm trying to send data (like a notification or something) to a nearby device without an internet connection. The restriction is that the device I'm trying to send data to does not have my app installed.
I've considered using Bluetooth, but the problem is that in order to send data, the external device needs to be running a server socket, which means it would need to be running an app as well.
Any suggestions on how to do such a communication would be greatly appreciated.
Thanks