If You are Busy or attending meeting and someone's call disturb you then you can get rid of them. You don't want to pick the incoming calls so you need not to worry about it .Switch off phone is not a solution of your problem, solution is to set caller to as blacklist add their number in caller blacklist simply by using Real Call Blocker 17. If you want to block all calls(Filter all calls), calls from unsaved contacts(Filter unknown calls), or block contacts from list then you can do this by using call blocker application. You can add numbers by simply click on button "Add Number".
>Easy to Use
> Block All Calls
> Block Call of specific number
> Block From Contacts
> Check list of block numbers.