icon missing iPhone

Hi Mac Friends...

The Green Dialer icon is not in my iPhone doc. 

I had my finger on the screen (as to move or delete apps), but I was unaware of it... I looked down and my dialer was missing from my dock.  

The thing is that the iPhone doesn't let me delete the icon, so where did it go???  Is there a way to find it?   

I checked all of my folders and other pages. 

Is there an easy way to locate or fix???

Thank you!