Some people use their phones as, you know, phones, but for many of us the "phone" aspect of a smartphone type thing is, while necessary, not exactly its most important feature. My landline is gone, so I need my gadget to function as a phone, but I hardly ever actually use it for the function.
Sweet spot: device which is small enough to conveniently fit in pocket or similar, not so large that it looks ridiculous if you use it as a phone, but otherwise as large as possible.
