I expect they think that a significant percentage of people that have Internet also have a smartphone. They probably aren't far wrong.

Your OS might be killing (outright or effectively) your app - check dontkillmyapp.com for possible solutions. Or the app doesn't have notifications enabled at the app and system level.

They are: ping 0xC0.0xA8.1.1 or 0x7F.1

Standard scanf number parsing is generally used though some OSes reject that.