The iPhone 4S is more than just a phone. It makes technology not only accessible to the common man, it makes it easy to use for anyone and everyone. A former neighbor of mine, who is completely blind, said that it's the best phone he's ever used, as the assistive technology built into the phone makes a device with no tactile feedback so easy to use.
This is my third iPhone - I had the original 2G, then upgrade to a 3GS and now the 4S. One of the most celebrated features of the new phone is Siri - and it is entertaining, helpful and on occasion, frustrating. I didn't give this awesome phone 5 stars because I do have some issues with it and there is always room for improvement - but it's by far the most feature-packed phone with the most usable interface available today.
With my 3GS and the latest iOS software, I could click and hold the clicker on the microphone portion of my earbuds and say "dial Jane Doe, mobile" and instantly, I'd get a reply back saying, "Dialing Jane Doe, mobile" and it would dial. Now ALL voice commands are routed through Siri online - there is a significant delay - and if there is a Siri outage (which admittedly is happening less and less), I cannot voice dial at all. I find that irritating. Very irritating.
The outbound camera is very high quality for both video and photography... but works best with bountiful light. The camera app doesn't do the best job on the front facing camera, yet another app I've used, Incredibooth, does a much better job in using that camera with higher quality photos... so I'm not sure if it's a hardware issue or a post processing issue. Unless I'm in very bright lighting, I find the front facing camera to be very grainy and low quality.
Most cases out there cause a white fog to show up in photos or video if you use the flash or light as it bounces back along the hole in the case around the glass back... so unless you have a case that has a giant hole in the back to accommodate the light, you may have to take the phone out of its protective case to use the camera in low light conditions where you need the light or flash. The light is very powerful and I've used it as a flash light more than once.
I use Siri ALL THE TIME - for finding specific retail places near by, to ask quick questions, etc. My 3GS was a 32GB, so I rode the fence on whether to get my 4S as a 32 or 64GB - I'm so glad I opted for the bigger model. I use various apps like AppShopper to find recently and temporarily reduced and free apps and download apps all the time to try them out. I simply wouldn't have the room on my 32GB for all I do. Because of the high quality of the video camera, I find myself shooting video quite a bit - and that high quality camera means high quality photos & video that can take up a lot of space really quick. That, plus all the podcasts I subscribe to - and I feel like I've got some room to spare... but things would have been a tight fit on just 32GB.
I got the AppleCare+ for my phone and it's already paid for itself. I initially rode the fence on getting the warranty since the price has gone up - paying $99 for a $400 phone seemed a bit like paying $2500 for a $10000 car - just too steep - but without the protection, a replacement phone would cost me an additional $299. Even though I have a case with a front flap to protect the glass, I dropped my phone on our caliche rock drive way - and naturally, it landed face down with the flap conveniently flying out of the way and shattered the glass. Because I had AppleCare+, I got the phone replaced for only $49.
Taking a photo and attaching it in an e-mail could not be easier. Apple really has thought of everything. Most geeks already know the features of the phone and the OS, but non-geeks wonder, "will I even be able to use it?" The answer is unequivocally, YES! The best test case is my mother, who also has a 4S - an upgrade from her first iPhone, a 3G. My mother will openly admit that she just got chiseled out of the ice just a few weeks ago. She's about as non-techy as they come. I literally have to go to her house to help her change the batteries on her TV remote control. She has zero mechanical or technical skills... yet she LOVES her iPhone. She uses Siri all the time, surfs the web and uses several apps. Of all the cell phones she's ever used, she readily admits that it's the most useful phone or device of any kind that she's ever owned. Prior to an iPhone, she never used an address book on her phones and never used any function other than dialing numbers by memory and receiving calls. In addition to the phone being fairly intuitive, the Apple Stores offer free classes all the time - including classes on how to use the iPhone. You can even take the class before you ever own anything by Apple - you just go to their site, look up the retail store near you and look up their class schedule.
The iPhone is a life changing device on so many levels. With the free "Find My Friends" app by Apple, my husband and I can keep track of where we are without having to call each other... and using that app, I can talk my mother through turns and other directions to get where she's going - because on the app - I can see where she is in real time. Whether I'm checking the weather, stocks, or sending an e-mail - it's by far the easiest interface that's ever been made for a phone.