title: Making a constant line between a dot and your finger
body: <p>I want to do a similar thing to what the app Scalar did, where they made a capability to drag from a point onto the notepad to paste the number to the location they draged the dot too.  What I'm really interested in is the line that stays connected to the dot and your finger as shown here: </p>
  
  <p><img src="https://i.stack.imgur.com/75upJ.jpg" alt="enter image description here"></p>
  
  <p>My problem is that I don't really know what this is called, so I am having trouble searching for how I would do this.  Does anyone know what this would be called, have any tutorials they have came across on this subject? And even better if you have some code for me to look at would be awesome. </p>
  
  <p>Thanks. </p>