Is there a way on Android to intercept incoming calls/SMSes to either block/unblock it?

Question

Is there a way to intercept incomming calls/SMSes (to block or unblock it) on the basis of mobile numbers which are added to screening list?

Answer 1

As far as I know the application for receiving calls cannot be modified. However, see How to block calls in android for some creative suggestions.

There seems to be a walkaround for deleting SMS see How to delete an SMS from the inbox in Android programmatically?.

But it is highly questionable for an application to do this, as the sideeffects could be severe. Make sure your users understand this! The best solution IMHO would be to have a separate build of android which supported these child-safety features (I assume that is what you want to use it for).