I have recently bought iphone 4. My friend is using whats app. Her number is stored in my contact list but i can not see her in whats app nor add her. How to do it?

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

you can download a call blocker app from the app store

Then just add the numbers to that app

Block someone from calling or texting you one of two ways:

1. To block someone who has been added to your phone's Contacts, go to Settings > Phone > Call Blocking and Identification > Block Contact. ...
2. In instances where you want to a block a number that isn't stored as a contact in your phone, go to the Phone app > Recents.

How to Block a Number on iPhone ' POPSUGAR Tech

www.popsugar.com/tech/How-Block-Number-iPhone-31863584 https://www.google.co.uk/webhp?sourceid=chrome-instant&rlz=1C1CHBD_en-GBGB719GB719&ion=1&espv=2&ie=UTF-8#q=How+to+block+someone+from+calling+me+or+texting+me

You can use the default application of IOS find friends. Send them a request and if they accept you and have the location services on, on their phone you can locate them.

You can block text messages via Messages app. This works really well for blocking text messages on iPhone, like some unknown spammers, advertising companies and internet marketers bothering you with promotions and offers for products that are not at all related to your interest. These steps will block only those unknown callers that you choose to block.
1. Go to the Messages app.
2. Tap on the target message from the spammer.
3. Choose "Details" on the top right hand corner and tap on it.
4. There will be phone icon and a letter "i" icon across from the number. Tap on the "i" icon.

5. Scroll down to the bottom of the page and then tap on "Block Contact".
Note: Once you press on Block Contact, the phone number that you just blocked won't be able to make phone calls, send text messages, or Facetime you.

How to Block Text Messages on iPhone

here they show 4 ways to block numbers on an iPhone:
How to Block Number on the iPhone

You can block any number on your iPhone by just installing an app called "iBlacklist"
In the app you have many options, and with them there's an option of blocking a cellphone number.

You go to Blacklists - General BL. There you have '+' in upper right corner. From there you can add the number you want from contacts, recent calls and messages or write it yourself.

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

Are you sure you've entered her number correctly? She might have to add you before you both show up on eachothers.

hi,i just restore my iphone,and next thing it can,t switch on,iphone couldn,t recognise my sim card and it shows only emergency and itunes sign in iphone.please help.