I am thinking about developing a personal application for me and my SO. What it does? It sends a simple notification:
Thinking of you, hope you are doing allright!
I want it to be send through data. The receiver should only get a notification if connected to data, for example like messaging in Whatsapp works.
The question is: What is the simplest way to make sure that both our phones are connected / authenticated? Maybe through signing into Google+? I fear that implementing a Google+ sign in would be way too complex / unnecessary for my Use Case.
Example: User A has this app installed. User B installs it too and A gets a notification saying that User B has this app installed. Now A can choose to request a connection. User B confirms and from then on, both can quickly send each other a simple notification.