title: Android WiFi Device-to-AP Round-Trip-Time (RTT)
body: <p>With Android <code>API-Level 21</code>, respectively 23 some methods to measure the Wifi <code>roundtrip time</code> (RTT) were added to the SDK:</p>
  
  <ul>
  <li><a href="https://developer.android.com/reference/android/net/wifi/WifiManager.html" rel="noreferrer">WifiManager.isDeviceToApRttSupported()</a></li>
  <li><a href="https://developer.android.com/reference/android/net/wifi/ScanResult.html#is80211mcResponder()" rel="noreferrer">ScanResult.is80211mcResponder()</a></li>
  </ul>
  
  <p>But I do not find any information how to use the API to measure the <code>RTT</code>. </p>
  
  <p>The relevant class <a href="https://android.googlesource.com/platform/frameworks/base.git/+/android-7.0.0_r6/wifi/java/android/net/wifi/RttManager.java" rel="noreferrer">RttManager</a> is still marked as System API.</p>
  
  <p>Is there any way to perform <code>Device-To-AP RTT</code> measurement?</p>