It's been an interesting couple of months for me, as I've been using a 4s and more recently a 3GS as my main phones, while spending a decent amount of time with the 5s and 6.
I have to say that I really think Apple got it right with the 3GS size and shape.
It is
by far the most comfortable to hold, and most secure in the hand of any iPhone.
After that, it is the 4s, the 5s, and 6 in that order.
Personally, I don't like anything larger than the 3.5" display. I can reach
most of the screen one-handed with a 5s/6, but the device is not that secure in my hand when doing so.
The flat backs and thinner designs mean that the newer models are not nearly as comfortable to hold as the 3GS, or as secure.
The 6 is worst in this regard, since the flat edges of the 4s/5s at least gave you something to grip.
The "thickness" of the 3GS is a total non-issue in my opinion. When you are holding the phone, it simply fills out the empty space which would be behind a 4s/5s/6 when you're holding it due to its curved back, and it's a lot more comfortable for it.
Of course, the 3GS and the 4s are both very outdated phones at this point. The 4s can run iOS 8, but it can be slow when running demanding apps, and most iOS7/8 apps are now designed with the extra height of the 5/5s in mind, so things feel a bit cramped.
If the screen was higher resolution, and there were even smaller font options, it would not be an issue though.
Until recently, I thought I wanted an updated 4s, but having gone back to a 3GS it turns out that it's an updated 3GS that I'd want.
Make it from aluminum to make it feel like a premium device, rather than the plastic of the 3GS, and give it all the internal specs of a 6 Plus. It's thick enough that you would be able to have the optical stabilization without the lens protruding from the back of the device.
I use my phone for listening to music, as a remote for my home music system, for email/iMessage/Skype, checking news via RSS, as a quick calculator/unit converter, as a stopwatch/alarm, to check the weather forecast. If I had a newer model with a better camera, probably for occasional photo/video use too.
I rarely ever use it for games, and never use it for watching videos. I have absolutely no use for a 4.7" display.
You say the small phones feel like a toy now. I say they're a tool.
The people wanting larger phones seem to be the ones using them as "toys" for playing games, watching videos, and killing time.
I want the phone to be as responsive as possible, so I do want to upgrade to a newer phone. I definitely want TouchID so that means it has to be a 5s or a 6. I really want 128GB (or more) storage for music, which would mean the 6. For now, I'm probably going to hold off and see what the 6s turns out to be. Maybe there will be a 6s mini, or at least a regular 6s with OIS.
The iPhone's camera has grown to be a serious contender in it's industry, and being capable of 1080p @ 60fps video recording, 240-fps recording and 43 Megapixel panoramic shots means people are using these things for actual filming. Professional photographers are giving this camera the time of day and Point-and-Shoot cameras are dead, all because of a sapphire covered lens the size of a tack.
I think you're giving it way more credit than it deserves. Yes, you can create nice photos with an iPhone if you have good lighting.
Yes, it's killed off point & shoot cameras - not because it is better, but because it's good enough that it eliminated the need for most people to use a separate camera. You still don't even have an optical zoom on the iPhone.
And you won't see a professional photographer
seriously using an iPhone camera for work, unless that's the gimmick for a book they want to publish. It may be one of the better cell phone cameras, but it's nowhere close to the quality of a dedicated camera. You can't even shoot RAW with it, and low-light photos look awful as a result.
