Now that I’ve (finally) given up my landline, and transferred that number to my cell, the number of robocalls and unwelcome calls has increased exponentially. If you’re really serious about limiting calls you don’t want, one option is to insert a request that the person confirm they’re human — that does work but also annoys normal callers. The other option on iPhones is, as detailed below, to simply turn on Do Not Disturb (in Settings) for anyone not already in your Contacts list. Some ideas to consider.