Exacq is a very good piece of software, and has a web interface that works just fine on mac. (also works to a degree on iphone). But that isn't needed, because they have a fully functional mac client as well.
The only drawbacks are they're a little expensive compared to the likes of NUUO or Geovision, and the software is 100% edge based. So it fully depends on the compression of their PCI cards, or on the compression of the IP camera involved. No capability for analytics, or in-software motion detection.
It also has very good audio support, particularly with their capture cards. Audio is 100% in sync with the video on playback.
-J