SweOper

This app is really only meaningful to use in Sweden since it will try to look up the Swedish operator for a given phone number.
There are options so automatically look up incoming and/or outgoing calls and whether to show a dialog after the call has finished. You can also manually enter a number to test.
For now, it will not even try to access your contacts since many users consider the combination with internet access a bad idea, but let me know if you want it anyway.
NOTE: No ads!