title: Android apps, communicating with a device plugged in the USB port
body: <p>I'm thinking about an Android app (with possibly an accompanying physical device), and I'm trying to figure out whether this is something that's feasible.</p>
  
  <p>1) Let's say I plug my Android to my PC. Would it be possible for an app installed on the PC to communicate with an app running in the cell phone? I just need a very simplistic data exchange, it can even be one-way (just data pushed from the cell phone to the listening app on the PC, whenever the cell phone wants, I don't need any data sent from PC to phone).</p>
  
  <p>When I plug it in, the phone gives me 4 options (charge, disk drive, HTC sync, tethering), which makes me think this is not doable, but still worth the shot.</p>
  
  <p>2) Would it be possible for an app on the PC to talk to an app on the phone through any other way? (Wi-fi, bluetooth, etc). I'm guessing no on wi-fi since neither party has the other's IP (and I want this to kinda just work, not having to input IPs manually all the time). </p>
  
  <p>3) If I make a device that's plugged to the little USB port at the bottom of the phone (and let's say this is a magical device that can do anything, I don't quite care about those details as long as it's doable). Can I have an Android app talk to that device?</p>
  
  <p>4) Any other ideas to make the phone talk to a "device" that I make, or to an app in the PC are more than welcome. Going "through the web" could be an option (although there'd have to be a central server that I own as a middle man, I believe). But I'd prefer if the communication was direct between the two devices.</p>