David Pogue got an iPhone before almost anybody, and he’s already written a 304-page book of tips, iPhone: The Missing Manual. O’Reilly will offer a downloadable version within the next three weeks and the printed version later this summer, but you can see a sneak preview right now.
I especially like this shrewd tip for prolonging battery life:
By covering the [ambient-light] sensor as you unlock the phone, you force it to a low-power, dim screen-brightness setting [and bypass] all the taps and navigation it would have taken you to find the manual brightness slider.
I wonder how much ability developers will have to exploit the phone’s other sensors in new ways. It would be cool to control widgets with the accelerometer and proximity sensor.