Apple Computer has just announced a cell phone that runs Mac OS X, called the iPhone.
You can go to http://www.apple.com and read all the details released so far.
The applications on the phone are centered on the Safari web browser, and email through Yahoo and Google. And of course storing and viewing iTunes and iPhoto and video.
The phones will have either 4GB or 8GB of flash memory.
There is no word yet on third party applications, although this is inevitable.
I'm predicting that before long there will be new audio recording and editing software, signal processing, and virtual instruments for the iPhone.
I'm also predicting that you could plug a USB keyboard into your iPhone and have a musical instrument for live performance, taking the place of a laptop computer.