The latest version of i48 has been submitted review by Apple.
This new version adds support for running the emulation at full speed (although that has some interesting effects on usability). I have also added theme support and included a theme based on Power48 provided by Fabrice Roux. Finally the buttons now highlight when they are selected making it a bit easier to use the keyboard.
I was hoping to add sound support in this release, but have decided to submit what I have now and work on the sound support for the next release.