I'll look into it how to make it multiplatform.

@ellipsis

Could you explain a bit more in detail? I would really like to port it with the least effort.

I also did some cocoa programming recently for iPhone and iPad so it could work, given that I have enough time
Also there are multiplatform frameworks available that target android and iOS. But i'll stick to the desktop version for now and make it platform independent... Challenging, but fun

Meanwhile, the app has a better scaling and overview of the orders on the left and the buy/sell buttons on the right.