The Phone size sinusoidal curve

Something weird is happening to mobile phones: After shrinking from enormous Zack Morris proportions in the '80s and '90s, they're getting bigger again.
So big, in fact, that some won't fit in jeans pockets anymore.
The Dell Streak, which is set to be released in the U.S. later this summer, is the biggest of the  phones so far, with a 5-inch screen. The screen of the iPhone 4, by comparison, measures only 3.5 inches diagonally.
When held up, the Dell streak looks like a book.
The Streak's mondo screen has become the focus of much debate on the internet, with tech bloggers arguing about what kinds of pants you'd have to wear to carry it around in your pocket; how big your hands have to be to hold it; whether or not people will stare at you when you're using it; and, perhaps most significantly, what exactly constitutes a phone these days.
Is a phone just any device that can make calls? Or does it have to be portable enough to carry with you, regardless of how baggy your pants are?
As mobile phone technology improved, there definitely was a trend for smaller and there definitely was a trend for thinner, but I think we're seeing the pendulum swinging back in favor of larger phones."

Several Android phones -- which run on an operating system developed by Google, as opposed to those by Microsoft or Apple -- have come out with screens that are larger than 4 inches diagonally.
The HTC Evo and the Motoroloa Droid X, for example, both have 4.3-inch screens. Sony Ericsson is rumored, according to the blog Engadget, to be working on another 5-inch smartphone, the same size as the Dell Streak. (As a side note, the HTC Evo is so big that it comes with a kickstand).
In video reviews of these ever-larger phones, it seems almost to be a requirement these days for tech pundits to try to shove the things in their pockets as a way to determine whether the devices are truly portable.

The other potential issue with large phones is that it can be difficult to hold them up to your face, depending how big your hands are and if your arms are strong.
When one tries out the Dell Streak their hand literally becomes tired and stretched-out from holding the phone.

Despite some fuss about the bulk of these 4- and 5-inch phones, there are some clear advantages to screens with more real estate.
As phones increasingly become internet portals, e-book readers and video players, having bigger screens makes them more useful.
Those functions are butting up against some long-held ideas about what a mobile phone is -- namely that it's a gadget that you can easily carry in a pocket and hold to your ear to make a call.
So maybe we need a new cell phone definition:

One that can be carried in anything including a gunia.