The perfect smartphone screen size goes according to depends on your personal taste

It's Is 6 inches screen too big ? Or 4.7 inches too small ? I think there is no a rule that fits everyone's taste.

15 years ago, the rule was "the tinIER the better" when it comes to cell phones sizes. To reduce the size as much as possible, was the goal that all cell manufacturers must had to reach if they wanted to survive in this competitive business. This was true in the pre-smartphones age. But all everything has changed since Apple introduced and popularized the iPhone. The cell phone screen was not used anymore only to visualize names and phone numbers: the new technology in those days began to show more and more kinds of diverse content on the device, and it fomented manufacturers to offer bigger screens. 

Nowadays, it's difficult to find smartphones on the in stores which where the screen is smaller than 4.5 inches. 6 inches are is the size for of the biggest smartphones that can be considered even phones and not phablets. In my opinion, 6 inches cell phones can show a lot of more details than smaller devices can't, but at the same time, they consume the battery more quickly, and it is impractical to operate with one hand. Even 5.5 inches displays are hard to handle with one hand, a feature that is quite estimated for those who used to have cell phones up to 5 inches and could manage well these devices well using only one hand. 

I'm convinced that a good size is between 5.1 and 5.3 inches, but again, this depends on your personal taste.