I like to know who's calling or who called me, even if it was a wrong number.
What it does
Simple, you enter the offending phone number or name, then it checks your contacts contacts to see if they have the number saved in their contacts. Assuming they also have the app. If they do it shows it to you.
How I built it
Um with Android Studio?
Accomplishments that I'm proud of
It works and I actually finshed it. I'm knackered, sorry.
What I learned
More ways to android.
You can test it with a single phone, and this is how the requests would look like. phone to server: I need this number/name server to all phone including original: Do you have this number or name in your contacts phone(s) to server: yes we do, here it is server to original phone: here you go.