title: Can a phone pretend to be a Bluetooth keyboard?
body: <p>It seems like it would be super useful if an app existed for iPhone/Android that emulated a Bluetooth keyboard or mouse. e.g., you turn on the app, and suddenly you can type on your iPhone keyboard and your PC/PS3/etc. pairs with it as if it were a Bluetooth keyboard and receives the typed letters.</p>
  
  <p>This idea seems so intuitive to me that I am thinking the only reason it doesn't exist is that it is not possible, but I don't understand why it wouldn't be possible.</p>
  
  <p>Is there a limitation of Bluetooth which prevents a device from emulating a different type of device? Or, perhaps, a limitation in the APIs exposed by iOS or Android which would inhibit this?</p>
  
  <p>EDIT: it looks like the iPhone Bluetooth APIs are fairly limited as you can only communicate with Apple-licensed accessories: <a href="https://stackoverflow.com/questions/4795962/is-it-possible-to-develop-an-ios-app-with-bluetooth-capabilities">Is it possible to develop an iOS app with bluetooth capabilities?</a>  This would presumably rule out anything along the lines of emulation of another type of device. The question is still open for Android though.</p>