Struggling to deal with spam calls on your iPhone or Android smartphone? If you don't want to keep receiving calls from unknown numbers, there's a simple method to "silence" them without actually blocking them. This allows you to look up calls from unknown numbers and contact them again, on a case-by-case basis. On this episode of Gadgets 360 with Technical Guruji, we show you how to silence unknown callers on iOS and Android without downloading any additional software.