My list of desired cell phone features includes a large screen, a world phone, and a physical keyboard. My current phone, the Samsung Note II, provides the first two. Its virtual keyboard is usable, but much less usable than an ordinary keyboard, or even the tiny keyboard on my old Psion PDA. It is possible that I could change that by training myself in Swype or something similar, but so far I have not done so.
The phone also has an alternative form of text entry—speech to text. It is surprisingly good but still, in my experience, much slower than typing. Possibly that could change with improved software and more practice using it, but there remains a more intractable problem. Text entry to the phone often happens in the presence of other people who would be likely to find my speaking to my phone distracting.
Which suggests an interesting possibility. Many people, mostly those who view cell phones primarily as phones rather than primarily as pocket computer/internet devices, access their phone through a bluetooth earpiece. Perhaps something similar could be created that would pick up words spoken softly enough to be inaudible from a few feet away and use them as the input for speech to text. That could, in principle, provide a form of text input faster and easier than typing—without requiring the additional weight and thickness of a physical keyboard.