Please note, the package does not contain the required ROMs for the emulator. You will have to obtain them elsewhere. If you don’t want to spend too much time fiddling with the emulator, just take a look at the album full of screen shots from old Apple games to the left. Please do not contact me for sending you ROMs or games - i won’t.
MacAddict even ran an article about the emulator. Guess was the first native MacOS X emulator:
I worked on Apple2 emulation on Unix/X11 quite a while ago and did a bit of work on a GL/Cocoa based emulator some years ago. In both cases, I started off with some existing emulator. Due to time constraints, I did not spend more time on it recently. Here I will try to put some of the stuff I did for download along with screendumps. Please do not expect me to spent too much time on improving it. Download it here:
OSXII: an Apple ][ emulator for MacOS X