Michael Loux's introduction to the issues of modality as addressed by the use of possible worlds gives a clear insight into the issues that face those trying to understand or use the principles of possible worlds and the difficulties that need to be addressed. The selection of papers shows the broad range of reactions to the approach.

Everything you expect from a Blackberry, and a touch screen too.

The screen rotates based on its orientation and there is an on-screen keyboard when text input is required. If you have a significant amount of text you will probably want to use the slide out keyboard. I'm surprised this slides out of the short side, rather than the long side to give larger keys, but as long as your fingers are reasonable nimble it works just fine. I'm surprised how little I use the keyboard.

For browsing the web, there is wifi connectivity as well as your mobile broadband connection, and it is easy to change between a full page view and a 100% view by double tapping the screen where you want to zoom in. Rotating the screen into landscape mode will also increase resolution. The overall screen resolution is 480 x 360 pixels, this is rather less than the I-Phone 4 at 960 x 640. The zooming features of the new browser mean you can work around this, but more pixels would definitely be an improvement.

As you would expect Google Maps works well with the GPS, and the usual office applications are available and you really can show a powerpoint presentation to someone on the screen. However, I had to buy a PDF viewer, which I think of as a necessity.

Overall, this is a very usable smartphone. I'm using it more for more things than my old Blackberry Pearl, and I venture out more without my PC than I used to.