I'm getting ready to start a project developing a mobile phone application utilizing the phone's camera and whatever other environment sensors are available on the device. Based on some code I'll be inheriting, it would be an advantage to be able to use C++ as part (though not necessarily all) of the project. I've spent some time looking at the development environments for the three platforms mentioned above, but I'm looking for some practical experience from hackers here. On which platforms is it easiest to interact with the camera viewfinder and other sensor data (GPS, gyros, accelerometers)? What's your preference?