How do I know it is working?

You have to test it.

If the Status screen in Simple Call Blocker indicates that the extension loaded successfully, then it is working, and it is blocking the number of phone numbers the Status screen says it is.

You can test if it is working if you have another phone to call your iPhone with.

  1. In Simple Call Blocker on your iPhone, add the phone number of the other phone to the block list.
  2. Use the other phone to call your iPhone.
  3. Your iPhone will not ring. (Your voicemail may pick up, depending on how it is set up.)

Note that iOS does not tell you when numbers are blocked.

Blocked numbers do not make your phone ring and do not show up in your list of missed calls. Blocked callers can still leave you a voicemail; there is nothing that a call-blocking app can do to prevent that.