title: ANDROID - Using wifi interface (no internet) for network call while connected with mobile data (internet)
body: <p>I am working with android device for POS system. I need to do data backup by uploading data to portable 4G router with tf card. In my device, I am getting internet from mobile data. There is no internet in my portable 4G router. I am only using it for backup purpose since my device doesn't have sd card slot.</p>
  <p>Ok <strong>please don't suggest anything other than my question</strong>. This is the proof of concept i need to prepared. Other alternative, my colleague and I are already brainstorming.</p>
  <p>DEVICE INFO</p>
  <ul>
  <li>connected with mobile data (have internet)</li>
  <li>connected with wifi (no internet)</li>
  </ul>
  <p>GOAL</p>
  <ul>
  <li>to use wifi interface to upload data from device.</li>
  </ul>
  <p>PROBLEM</p>
  <ul>
  <li>network call only using network interface with internet. In my case mobile data. I have no idea how to use wifi interface to make network call instead of using mobile data interface.</li>
  </ul>
  <p>IMPORTANT</p>
  <ul>
  <li>device must always connected with mobile data and wifi</li>
  <li>cannot put sim card to wifi router. This is to prevent portable 4G router from being used as hotspot after working hours.</li>
  </ul>