This is just a brief discussion on what I consider to be the various phases of mobile technology. Apple has probably already thought of most of this, but it is still interesting to discuss. I. Mobility The first stage and easiest challenge in mobile technology to overcome is the hurdle which requires us to remove the computer from a direct power source and replace that power source with an internal battery. Computers of this type offer mobility, but the mobility afforded is hampered by some usability issues such as unnatural controls and complex user interactions (which also plague immobile computers). II. Usability The second stage in mobile technology is to create a device that, despite lacking natural interoperability, it is easy to use, has a profile that makes it convenient to carry and has a more realistic battery life. The iPhone is the best example of such a device. III. Device Interoperability The third stage in mobile technology is to create devices which are aware of other devices and naturally interoperate with them to achieve greater functionality than could be achieved with either device acting alone. In short, it is the stage where hardware no longer needs operating system specific drivers because a type of artificial intelligence is developed between each device that enables each device to freely communicate with other devices, sometimes by protocol experimentation, where necessary. IV. Sensory Interoperability The fourth stage in mobile technology is to create devices which can easily interact with our own senses. A mobile computing device would be able to interface with vision, hearing and speaking, touch (a sensory network over skin) and even taste and smell. V. Host Interoperability The fifth and final stage in mobile technology is ultimately to create nanotechnology which can influence our own computing experience from within. Since this technology would literally exist inside our own bodies, it would go beyond just being able to provide an internalized computing experience. This stage is the holy grail of mobility technology. It will truly enable you to imagine any reality or experience that can be experienced (and even some that are less feasible in reality).