As you might know, nearly a half of all incoming calls are spam nowadays. Telemarketers use various tricks to get to you: sometimes they change the phone number to a local one, another time they try to hide the number to make you curious about who is calling you from private number and answer. The only goal, as a rule, is to sell you some product or service.
In most cases it is reasonable to block anonymous callers, especially on your child’s mobile phone. In the latter case, you should do your best to protect children from the threats and evil jokes that often come from unidentified callers. First of all, you should always remember one simple thing: if you get an incoming call and the number is hidden, the callers have certain reasons to stay anonymous. Personally I never answer calls with “No caller ID” and try to block them if my current phone gives me such an option.
Here is our step-by-step guide on how to block annoying calls from unknown phone numbers on Android. Below you will find detailed guides on how to do this on various devices running different versions and ROMs including stock Android, OneUI, OxygenOS, EMUI, MIUI, etc.