I have a rooted galaxy j5, android 5.1.1. I want to block certain numbers calling my phone. Is there a way to make the callers think my phone is shut off or dead?
Actually there isn't. Your phone doesn't get the caller ID until AFTER the first ring (that's how the telephone system works), so they can be cut off after the first ring but not before it. Your phone should have a call log. Find the number you want to block (in the logs), long-press it and choose Add to reject list.