How to Block incoming calls without third party apps- 2

You can block one or more phone numbers using this trick.

If you try to block calls sometime your network carrier will apply charges for this.Else you are using a third party app it will always running in backgroud and take ram,cpu and more issues.Some apps block calls after ringing.

This will help you to block calls without any app.

 Go to phone book.Now create a contact( you can give it a name like 'blacklist' or any other name.) and add phone number or numbers what you want to block.
Now scroll down.Then you can see a check box like 'send calls directly to voicemail'. Tick and save it.

When that person call you,call will be diverted to voicemail number.

If you want to completely block him or her,
  Go call settings> Voicemail settings under voicemail give  a wrong number(like 1234567) and save it.He will not disturb you again.

How to Block All incoming calls without a third party app

It's not a magic.
This is an easy way to block all incoming calls without any third party application.

Go Settings>Call Settings>Call forwarding


Now select ALWAYS FORWARD under the CALL FORWARDING.

Type a wrong number(you can use disconnected phone number or any other wrong number  here ) and save it.
When some one call you it will be forward to that given wrong number.

Now no calls!