The Seven Design Criteria That Shape a Mobile Device.

Here's the seven major constraints that govern the choices made byhttp://www.blogger.com/img/blank.gif an engineer in designing a cell phone.

The essential trade-off in any cell phone is compactness versus usability. We want a small phone, but we also want one that fits our bodies. Here's three solutions. A hinge. The classic flip phone - put a hinge in and change the size and it allows you to have larger keys. You can also see this same idea in slider keyboards. Second, you can do what they do on this phone - a Blackberry - and maximize available space by using very tiny keys. And, you can use software.

Bill uses a pile of old cell phones to show the seven basic design constraints that shape a mobile phone. You can find a transcript of this video at http://www.engineerguy.com/videos/video-cell-02.htm.