The reason the iPhone 4's screen is 3.5 inches is because the iPhone 3GS was 3.5 inches is because the iPhone 3G was 3.5 inches is because the original iPhone was 3.5 inches.
A consistent platform is a huge deal. The whole point of the iPhone is that it's touch friendly. Part of the iOS user interface guidelines is making sure touch areas are the size of a finger tip. This is heavily emphasized.
If there were different sized iPhone screens with incompatible aspect ratios this guideline would be meaningless. An app that has finger sized touch zones on a 4.3 inch widescreen phone would not on a 3.5 inch standard screen phone.
Apple's designers know this. It's on purpose. And Apple's designers decide what its devices look like. That's why the iPhone 4 has a 3.5 inch screen.
If you want to wonder why the original iPhone had a 3.5 screen, you've got to go back to 2007 when everyone else was still trying to copy the Blackberry. A 3.5 inch screen at that time was already unprecedented.
I don't doubt Apple prototypes iPhones with different screen sizes and there is pressure to upgrade. But the fact Apple has not just shows how reluctant it is to break with consistency. If Apple moves to a new screen size, I think it will have to be larger for backward compatibility with old apps. I highly doubt it will go smaller, ever. All old apps would suck on a smaller screen, and Apple doesn't deliver sucky user experiences. And if it does go larger, it will be a big deal. I wouldn't expect a new screen size for a long time after that.
They've also locked themselves into a resolution, in some sense. IPhone apps, unlike Android apps, are built using absolute coordinates. Developers can make assumptions about the width and height of the screen. And widths and heights are described, believe it or not, with floats, not ints. They've been able to maintain compatibility between devices because they've doubled the resolution every time they wanted to increase it. This has in some sense made life easier for developers, while it's allowed Apple to not build the UI abstractions that Android had to. It seems fundamentally unsustainable though, surely they can't keep doubling forever?
Does this mean that you haven't seen a desktop OS UI that doesn't look like crap? All desktop operating systems have to deal with different resolutions as they have to support different monitors. Even laptops generally have a video output for a second, unknown-sized monitor.
Ah, I see what you mean. Yes, fair call - you see this a lot in games, where the interface is based off static images - as you increase the resolution for better main view experience, the UI shrinks along with it, and it's tough if you like a high res main view but want larger control surfaces.
That being said, I have seen some games with nice UIs that scale appropriately with resolution, that is, changing resolution doesn't change the screen size of the controls. I can't for the life of me think of any at the moment - they're not that common, but they do exist.
OSX is not resolution independent, the UI shrinks when the resolution increases. This is not the case for Windows 7 (and older versions) though, dont know about Linux.
True, but it's the absolute size (in pixels) that matters on the desktop because the mouse (a pixel precise) pointing device is used. This becomes a problem on touch based devices with limited screen real estate where balancing info density and usability is crucial.
A 3.5 inch screen at that time was already unprecedented.
Supposing that is true: so was a 3.6" screen. Your story does not explain why the 3.5" was initially chosen instead of 3.6".
It's not productive when a commenter completely ignores an argument and instead proposes his own theory, without considering that the arguments need not be mutually exclusive.
Retina was Apple's "screen size upgrade" for the forseeable future. The devices like the Sensation and SGS II have screen resolutions of 800x480; 480x320 just wasn't going to look good next to them. Apple's stuck at 3.5" like you mentioned, so to compete with the new high-resolution (and larger screen, as a result) devices, they doubled the iPhone 4's resolution, which is a pretty decent compromise. One of the benefits of increasing resolution without increasing the display size is that your DPI skyrockets, and they jumped on that and marketed the crap out of it. The display looks "better", even if it's not larger. I would be genuinely surprised if Apple released an iPhone variant at >3.5". They might release an iPod Touch around ~3.75", but that's as high as they can really go before the 3:2 aspect ratio starts to make the device width prohibitive.
In order to maintain "Retina" display, they'd need to keep their 300 pixels per square inch or more density. That also doesn't leave them a whole lot of room to bump up the screen size without bumping up the resolution again. They've got some small room to play with in terms of the screen bezel though, so we could see a screen size bump without a resolution bump that still offered both the 300 ppi and the ability to touch all of the screen with one hand. (Think about some of the "iPhone 5" leaked images). Time will tell.
They can maintain that "retina" claim as long as the marketing department gets away with it. I think they can easily get away with that down to 200 pixels per inch or so (anecdata: I am myopic, but cannot really see the individual pixels on an iPad 1 Or current iPod touch)
I guess that the extra wiring needed for retina resolution means that you need more backlight to get the same display brightness. If so, one way to market a slightly larger display with say 250 pixels per inch would be by stressing it as having better battery life ('easier to see for the elderly' would work, too, but such a line does not fit Apple's image well)
Your prediction that Apple will not switch to a smaller screen size is illuminating...
The problem as I see it is that for marketing pressure they could switch to 4 inches displays, and the issue showed by the original poster is a bad one for smart users interacting with their device with just one hand (this is at least how I use it and how I see all my friends interacting with it).
Actually the iPhone software keyboard appears to be designed for a good one hand interaction since it works incredibly well even when you think you are putting your thumb in a too wide and imprecise area but actually you end pressing exactly the intended letter.
If there was a reason for the original display to be 3.5" is likely exactly that: the largest screen that is possible to get while preserving one hand interaction and reasonable size for holding it in your pocket.
Yup. Today's smartphones (and even tablets) are pretty much rebadged PDAs. The only advances have been a stylus-less UI, a vastly improved image (PDAs are for stodgy business men), and realizing that a package manager is a really good idea.
That's like saying 'the only difference between driving a car and riding a horse is that you feed the horse hay'. Not having a stylus makes a world of difference, both in how easy it is to use (using a stylus sucks donkey balls, and I did it for 10 years (using a stylus, not sucking donkey balls)) and what you can do with it (e.g. swiping is, in practice, impossible with a stylus)
And the switch to non-stylus screens required vastly different screen tech, so it's not like Palm in the 1990's just made an unfortunate choice and they could've switched at any time.
I lost my PDA stylus years ago. Adjusted the setting slightly and my finger worked fine. Palm did not need any radical new tech to hypothetically make touch.
Apple did need a different tech (transparent capacitive touch) for multitouch. But stylus-less finger friendly touch screen interfaces were around for 20 years before the iPhone.
The multiple finger manipulation was innovative and an improvement. (Though the Synaptics touchpad driver permitted basic multi touch years earlier.) Finger-based UI was not innovative and has a long history before Apple.
I don't know about you, but before the iPhone, I hated touch screens. Before the iPhone, most people have only been exposed to touch via shitty kiosks, credit card readers and ATM machines.
I remember the skepticism around Jan 2007 when the iPhone was announced. They said, "Pure touch? No way. Won't work. You need to have a keyboard." I was one them! Even I said, "yeah, the UI is pretty, but the touch screen probably sucks." However, once I played around with my first iPhone, I bought one the next day based purely on the amazing performance of the touch keyboard.
Pure touch phones already existed in 2007 before the iPhone, but they sucked donkey balls. In fact, many of them still do. To downplay the iPhone's touch UI is disingenuous. To this day, the iPhone still has the best touch response on the market. Followed by WP7, WebOS, Android and lastly BB OS in that order. I own an iPhone, WP7 and a Nexus One and use them everyday. Typing on Android is like eating fried chicken with a chopstick.
Well I'm not sure what kind of PDA you were using then, but all the Palm, Handspring and various Linux ones (can't remember what they were called) that I used worked only with a finger when you used your nail, and even then there was no telling what exact 'touch point' the screen/OS was going to use.
It's much like today's TomTom devices. They are advertised as being 'touchscreen', and the UI is designed as such (with big buttons etc) but they're still a bitch to operate. I mistype at least 20% of my interactions with it, and like I mentioned I have a decade of experience with working around finicky touchscreen technology (as much as I hate to admit).
I'm not saying you or anyone else wasn't able to operate a previous-generation touch screen with their finger, but the experience simply wasn't good enough to make it mainstream. For example an on-screen keyboard is/was out of the question on a Palm.
Hold an iPhone in your right hand with your fingers wrapped securely around the device. Now type Q with your thumb. It's perfectly comfortable for me. But if I try to reach literally any further, I can start feeling a tightness in the tendons of my thumb to stretch further.
It really is the perfect size for me, and I'm a 6'0" lumberjack of a human. Any bigger and it would be less comfortable to use.
A consistent platform is a huge deal. The whole point of the iPhone is that it's touch friendly. Part of the iOS user interface guidelines is making sure touch areas are the size of a finger tip. This is heavily emphasized.
If there were different sized iPhone screens with incompatible aspect ratios this guideline would be meaningless. An app that has finger sized touch zones on a 4.3 inch widescreen phone would not on a 3.5 inch standard screen phone.
Apple's designers know this. It's on purpose. And Apple's designers decide what its devices look like. That's why the iPhone 4 has a 3.5 inch screen.
If you want to wonder why the original iPhone had a 3.5 screen, you've got to go back to 2007 when everyone else was still trying to copy the Blackberry. A 3.5 inch screen at that time was already unprecedented.
I don't doubt Apple prototypes iPhones with different screen sizes and there is pressure to upgrade. But the fact Apple has not just shows how reluctant it is to break with consistency. If Apple moves to a new screen size, I think it will have to be larger for backward compatibility with old apps. I highly doubt it will go smaller, ever. All old apps would suck on a smaller screen, and Apple doesn't deliver sucky user experiences. And if it does go larger, it will be a big deal. I wouldn't expect a new screen size for a long time after that.