As we all know, 20,000+ users downloaded Call Security latest version on 9Apps for free every week! It works great even on 2G. This hot app was released on 2017-11-28. Here are some guides of this app:
Call Security is an android app designed to provide users with call privacy features. It has password secured call receiving. The user can secure a contact with a password to restrict others from calling without the know how of password. It has additional features like removing recent password protected contacts from the log.