Hello,
You will find the available emulators on the
Emulators page.
Simbuino only work on windows, by you can run in on a mac using a virtual machine.
Gbsim should run on mac but the available binaries are only for windows so far, so you have to compile it yourself for mac. If you do so please share !
RetroMicro is browser based so you should be able to run it on any platform. Still in early development though.