"When is a phone not a phone?"
When it doesn't make/receive phone calls!
Seriously, they are all 'phones', but the 'phone' evolutionary tree has been forking all over the place in recent years. Only one branch of which are still just 'phones'. Mobile devices that make/receive calls and the occasional text.
All other branches of this tree have grown in different directions. Some more business-centric, some media-centric, others in other directions. For instance, phones that been developed as (almost) strictly SatNav devices. Most of these branches sprouted off due to different user demands. Now that we KNOW phones can do more than we expected 5-6 years ago, we all want them to do different things.
This branch, the one Steve's discussing, is the one where people wanted larger screens built onto heavy duty, multi-use devices. I blame the Iphone for this. Apple produced a big TOUCHABLE screen that had a QWERTY keyboard and the ability to *gasp* watch movies, in a reasonable resolution (and frame rate!). Since then, this new branch of the tree has just shot up.
Now there are a mulititude of large screen touch phones. And some are getting larger than others.
Are they all getting too big? No, i don't think so. With the increasing number of features and options being shoehorned into most 'modern' mobile phones it's only logical that they increase in size. Especially being one of the most common features being touchscreen. People want the real estate to be able to work on their screen. How many of you are still using 15" monitors (by choice)? Another feature is media and games. People want a bigger screen to watch movies and play games. A lot of phones (the good ones anyway!) now have hardware graphics accelerators, just for this purpose. And of course we're all now accustomed to surfing almost full size, flash enabled web pages.
But this is only one branch on the family tree. For those that don't want/need a large (huge) screen there are plenty of other options.
As far as one handed use, perhaps i have large hands, but i can use my Samsung one handed (one thumbed?) for almost anything. If i switched to a T9 display instead of QWERTY, i'd don't think i'd ever need to use two hands.
Is it a pain to have to use a phone two handed? Not for me, but i made a concious decision to accept that, if i wanted a phone as big as the one i have, with a QWERTY, that i may have to use it two handed.
Does the phone 'feel big'? No, not really (to me). But then i'm coming from an E90 and i have a TP2 here at work. When the Samsung is in my pocket i have to keep checking it's there!
Victorinox make a Swiss Army Knife that has one blade, a can opener, and a screwdriver. They also make the 'Champ', which has EVERYTHING!. The Champ is 4 or 5 times the size of the basic model, even though it also has the same basic features that you require in a pocket knife. I've had a large, heavy, often two hand required, Champ on my belt for 18 years.
Finally, look on the bright side. If Apple hadn't created their version of a large screen tablet form factor, we might all be walking around with HTC Advantages! 😮