title: Sync custom calendar with Android & iOS
body: <p>My boss ask me to create a website where they have a calendar and they can manage their travel agenda. This part is done and working well.</p>
  
  <p>However, now, I did some researches and I did not really get answer to my question...</p>
  
  <p>I am trying to find <strong>How to sync my calendar website with an Android OS and iOS (native calendar app) ?</strong></p>
  
  <ul>
  <li>Is there a sort of API or custom command wihtin both OS ?</li>
  <li>Would I need to write my own application ?</li>
  <li>What do you suggest ?</li>
  </ul>
  
  <p>Thanks.</p>