They already have your number if they’ve called you. But if you have an iPhone it has call blocking available. I use nomorobo with my provider and there is an app called HiYa that helps. You can’t completely eliminate them, but putting a little effort into it reduces them. If your provider has nomorobo, it’s cool. If the spammer has been put on its list, your phone will only ring once then the offending call just goes away.I am getting lots of spam calls so I want to get a call blocker app, though I read by doing so it somehow reveals your number to the spammers? How does this work? Am I missunderstanding it? Are there other privacy issues?