title: How to get the accurate position in the room on the smartphones GPS or blutooth or another?
body: <p>I would like to make an application in which:</p>
  
  <ol>
  <li><p>There are many tables or showcases in the big room like convention center.</p></li>
  <li><p>When you approach one table, one wave sound plays.</p></li>
  <li><p>When you approach another table, another wave sound plays</p></li>
  </ol>
  
  <p>Is it possible to make this happen on smartphones?</p>
  
  <p>I guess the GPS is not accurate, I should use blutooth or something,is it correct?</p>