Block incoming call iphone 5 - Apple iPhone 5

Android:

• From the call log, you can disable incoming calls from specific numbers.
• Select the number you want to block, then hit More or the 3-dot menu icon in the upper right corner and choose to Add to reject list.
• This will disable incoming calls from specific numbers.

iPhone:

1. To block someone already added to your iPhone's Contacts, go to Settings > Phone > Call Blocking and Identification > Block Contact.
2. To block a number that isn't saved as a contact in your phone, go to the Phone app > Recents.
3. Click the exclamation mark next to the number.
4. Scroll to the bottom and select Block this Caller.

The video for Android:

The video for iPhone (couldn't find a more updated vid):
And, finally, here's the source article for Android: Block Numbers And Texts ' Block Someone On Android

For iOS: https://www.popsugar.com/tech/How-Block-Number-iPhone-31863584

In Nokia Lumia you can add contacts to block number thereby blocking incoming calls from them.

Unknown callers should have a number that appears with no name - these can be blocked post call or in the Settings/Phone/Blocked Callers section. Unknown calls with no number can only be blocked from the carrier side - you would have to contact your provider.

go to settings\sounds\new mail \ and select a tone.

not an expert on iphones but I suspect you have do not disturb mode activated on your iphone and the one caller is on the accept list feature of do not disturb
http://ipod.about.com/od/phonefeatures/a/Using-Do-Not-Disturb-On-Iphone.htm

try switching off the silent button at the left upper side of the iphone

Go to Settings>>Phone>>Blocked on your iPhone to check out all the blocked numbers. for more details visit: How to Block Numbers on iPhone and Find Blocked Numbers on iPhone

Many iPhone owners expect that incoming call blocking is a built-in feature of the iPhone. Unfortunately, this is not the case. Such a feature is controlled at the provider level. Furthermore, most providers fail to offer call blocking to their customers. Providers that do often charge an exorbitant rate for this feature, such as AT&T in the US which offers a service called "Smart Limits" which includes call blocking but comes at a pricey $5 per month.

There are a couple solutions/workarounds that you can implement:

1) For those of you that are jailbroken, there is an appcalled iBlacklist that will allow you to filter incoming calls and SMS text messages. This is not a free app, but at it's current price of $12.00 (one-time purchase), it can pay for itself fairly quickly vs. pricey provider solutions.

2) Don't block calls, but silence them with a silent ringtone. This will still allow the calls to come through, but will silence the ring so you won't even notice. To set this up, download this iPhone silent ringtone (be sure to right-click or cmd-click and "Save As"), import it into iTunes, and sync it to your iPhone. On your iPhone, add the number you want to block/silence to your contacts and set the silent ringtone as that contact's custom ringtone.

You can't block incoming unknown calls, but if you don't accept the call, you will not pay for it.

You can't unless your carrier can on their side. Call them and ask