Tech Q - how to block all calls not in contacts, & No Called ID calls?

[Blue3]

Hey,

I have an iPhone5c with Verizon.

Does anyone know how to block all calls not in your contacts?
As well as all calls with No Caller ID?
Or at least make them go to Voicemail automatically?

I blocked the phone numbers of these 2 really nosy people, told them my phone broke (I have to see them in-person through work for 2 more months), but I have a feeling they will try to call me from another phone number to test if my phone is really broken or not.



I figured someone here should know!

[True Federalist (진정한 연방 주의자)]

I have an old fashioned flip phone and somehow I ended up with someone I don't know repeatedly butt dialing me.  I downloaded a silent ringtone and assigned it to that number, but even if you don't have the option to be selective in who you answer, you should be able to make a silent ringtone be your default ringtone, tho you'd have to make sure all your contacts don't use the default ringtone which could be a bother if you have a lot of contacts.