Using a 4" phone is this day and age where iOS itself is optimized for larger screen with gorgeous typography and higher resolution imagery is nothing short of boring.
Sure, it works and you can get (some) stuff done, but forget about working on documents or editing movies unless you want to squint.
4.7" is a nice sweet spot, but I went from 4" -> 5.5" without any regrets. Jailbreaking solves the one handed issue when I don't hold my 6+ with both hands (OneHandWizard tweak), and the benefits of a larger screen far outweigh the negatives (harder to fit in pocket). I thought I'd never get used to a larger screen, but now I would never go back to a smaller form factor than 5.5" (higher would also be too much).
Sure, it works and you can get (some) stuff done, but forget about working on documents or editing movies unless you want to squint.
4.7" is a nice sweet spot, but I went from 4" -> 5.5" without any regrets. Jailbreaking solves the one handed issue when I don't hold my 6+ with both hands (OneHandWizard tweak), and the benefits of a larger screen far outweigh the negatives (harder to fit in pocket). I thought I'd never get used to a larger screen, but now I would never go back to a smaller form factor than 5.5" (higher would also be too much).