Create os x application for real time Arduino control and data graphing

Hi all,

Currently i'm working on a project to control a rc plane. The goal is to completely control the plane by a pre-set flight path by an Arduino. From take-of to touch-down.
Because this is a pretty ambitious project I want to do this project in several parts. The first part is to gain all the accelerometer/gyro-meter data, clean this with a kalman filter and sent this to the ground.
What do you guys recommend as platform to create the application for read and save the received data, plot this real time and sent commands to the Arduino. The commands are like 'rise for 10 meters'. The Arduino will control the plane, not the computer.
I have some PHP and matlab programming skills. Next quarter I have to learn Delphi at university, I don't know if it's possible to make a Delphi application which can do this. It would be nice if the application works natively on os x, but also on windows.
What can you all recommend, and what is the best way to learn this language?

Thanks!
Bart

Any programming language that can read from and write to the serial port can be used. Objective-C has this ability.

Creating the real-time graph is an exercise in graphics manipulation. I can't comment on how easy or difficult that would be in Objective-C, since I've never tried that. Given the amazing things that Mac and iPhone and iPad applications can do, graphics-wise, I don't think it is a difficult task.

what is the best way to learn this language?

Same as any other language. Practice, practice, practice. When you get pretty good, practice some more.