Cell phones and the Internet have both had the effect of making the world a black place by blank communication speeds

I believe the answer is: better/faster; Increasing

Increasing communication speed allow people from different countries that are separated thousands miles apart to communicate directly and addressing a certain issue.

This would allow people to achieve better understanding on each other's situation and reduce the amount of conflicts that could occur.

Cells phones and the internet have both had the effect of making the world a better/faster place by increasing communication speeds.

It depends on how you view these technologies as other answers would also probably be correct but generally it is true that they made the world a better/more connected place by increasing communication speeds.