title: Dynamically create markers in OpenLayers 3
body: <p>I'm developing an application that loads lots of markers in OpenLayers 3.
  However, I would like to dynamically display and load markers while user is panning at a certain zoom level.</p>
  
  <p>Could someone provide me an example, or directions to do that?</p>
  
  <p>For instance, I would like to first create an example that drops a marker where user has clicked on the map.
  So, with this information, I will be able to handle the rest and post my solution here.</p>