title: Asynchronous synchronisation
body: <p>I have 2 async tasks:</p>
  
  <ol>
  <li>I'm getting user's location;</li>
  <li>I'm getting list of events from my API using Retrofit;</li>
  </ol>
  
  <p><strong>My question:</strong> How do I set an action only after I get successful result from both methods?
  Thank you.</p>