How does call blocking app work with conditional call forwarding?
RoboKiller uses a combination of carrier network (PSTN) and Voice over IP (VoIP) to deliver calls to your phone.  The technology and how calls are received on your phone are determined by the iOS version the device is running when RoboKiller is set up.  If you upgrade your iOS version, it is recommended that you disable/deprogram your phone, uninstall, and reinstall RoboKiller to ensure you have the best experience. You can find instructions on how to disable/deprogram RoboKiller in the Settings menu of the RoboKiller app.