MIFI: How to I start a script after Cellular connection has established

Any good idea on how to run the script after Cellular connection established?

Maybe using hotplug script

/etc/hotplug.d/

You can refer to other script. For example

#!/bin/sh

. /lib/functions.sh
. /lib/functions/network.sh
[ "$ACTION" = "ifup" -a "$INTERFACE" = "wwan" ] && {
  # do something 

}

Thank you. That works.