This tools intended to verification if phone number is online, offline, or airplane by sending Silent SMS (SMS that not pop up notification to destination phone number) but in programmable bulk through API Ktor.
This program and payload is based from itds-consulting/android-silent-ping-sms
Grant manually, app permissions otherwise it didn't work.
Send the payload through your ip addres that appear in the MainActivity with phone have prefix country number otherwise it didn't work.
{"number": "+628123456789"}
There's chance that this silent sms payload could pop up in certain device condition, like maybe modern Iphone with using eSIM or older device that is not Android.