How to Cut Down Spam Calls and Robocalls on iPhone and Android

Robocalls are cheap to run, and scammers can fake caller ID to make calls look local, so most people get them regardless of who they are. Answering even once can mark your number as active and bring more calls. Registering with the US FTC Do Not Call Registry or the UK Telephone Preference Service, both free, stops legitimate telemarketers, though not criminals. iPhone and Android users can silence unknown callers, block specific numbers, and turn on built-in spam filters that improve as more calls are reported. Carrier-level filtering from providers in both countries can add further protection.