I am sorry for the delay Moe, have been in a busy month.
Maybe you guys have already figured it out, but the difference between PhoneDrone and APM2 is that PhoneDrone doen't have the IMU shield. Basically, both are Arduino boards, in which you use the arduino IDE to program them.
The APM2 was design in a way that you can attach an IMU shield, with accelerometers and etc. The PhoneDrone, on the other hand, was design so you could communicate with an android device using google USB acessory APIs (
http://developer.android.com/guide/topics/connectivity/usb/accessory.html).
You don't necessary need the APM2 to use the Arduplane codes, you could adapt an adruino mega, but DIY Drones made that way to facilitate the process.
The idea behind the PhoneDrone was to replace the IMU board with the android device. That way, you could have great quality sensors and an enhanced processing platform.
I used the PhoneDrone + Android in a quadcopter. The main idea was to use the mobile 3G conectivity to replace the RC communication, expanding the reach (in a sense, we tried to replace the antenna truck of an military drone with the antennas of the mobile network). After all, the project wasn't sucessful. First, because of time issues, we just happened to use the ArduCopter code with and APM2 to control the motion, wasting the sensor capability of the android phone. For second, the conectivity was an issue, mainly because of the ping. The commands took too long to reach the drone, making the control really hard. But it was fun to make it. For controller, we made an web page with and realtime feed of the camera streaming from the Android, and using firefox gamepad API (
https://wiki.mozilla.org/GamepadAPI). Maybe we could make it work with the next gen mobile network.
I liked you project, will try to follow the progress. If you want to use the Phonedrone, a good starting point is the codes that Mr. Falko once posted in the group. It was really helpful making me understand the communication with the android device. You can also contact me at enricodvn at gmail.
Cheers.