I'm one of the original moderators of this site (and Cliesource) and someone who has used Clies ever since the very first S300. I have owned 6 Clies in all (S300, S320, NR70V, NX70V, NX80V, and the TH55, plus an SJ model that my wife used). I have been using the TH55 for over 3 years now, lamenting the fact that there was nothing in the PalmOS world that made me want to change and trying to figure out what I was going to do, since my screen is getting a little scratched and my formerly great battery life is getting to be barely adequate.
I used to be a total Clie power user, but with other responsibilities and boredom, I have been only using my TH for the basics over the past couple of years. I heavily use DB5 for my calendar, Netfront at night to read news articles in bed, ClieMail to download my work email to read at night and in the morning, Clock+ as my alarm clock wherever I am, occassionally use HandyShopper to reference lists I had previously made, occassionally use the Clie Organizer notes program to make little handwritten reminders with alarms, use SplashID to look up usernames/passwords, and use Docs2Go to check a few tiny spreadsheets that keep track of some things I need for work.
I provide the above to allow some perspective of what kind of user I currently am and the needs that I have. My cellphone is a very basic clamshell Sprint model, also with the battery going bad, and I have a 30GB video iPod that I use in the car, at work, and on trips.
I got the iPhone on June 29th, the first day. I left for vacation the next morning, camping in upstate NY, and returned last night. I had no access to Wifi most of the past week, but I do have a Wifi network at my house that I've used the first day and today.
This is just a mini-review, so I'm not going to go into great detail, but rather hit on some highlights of my experience. If anyone wants more details, ask, and I'd be happy to share.
* First off, the iPhone will definitely replace my cell phone, iPod, and my Clie. I was hoping for this when I bought it, but I wasn't sure it could cover all 3 adequately.
* The interface of the phone is amazing. Everything is so smoothly integrated, and it just works. From the campground, someone emailed me with their number included, and asked me to call them, and all I had to do was tap on the number.
* I was nervous about the AT&T network, but those fears have proven to be unfounded. Call quality has been great - people on the other end can't tell the difference between regular and speakerphone mode and have said that I've sounded very clear. I got coverage in a state park 10 min south of Ithaca, where my friend's Verizon phone would not work. The Edge network has also worked much better than I expected. In the town of Ithaca and at my house outside of Brighton, MI, Edge has actually been very fast. Wifi is obviously faster, but everything loads in a few seconds on Edge. At my campground about 20 min outside of Ithaca, the network was slower, but not untolerable, and it was pretty cool to be connected while camping. It was easier to dial my favorites on my old phone by holding down one number - on the iPhone, you have to hit the Wake button, do the slider on the screen, then hit your contact (if you were already in Contacts - otherwise, have to go there too). This doesn't take that long, but isn't as easy as holding down the 5 button until it dials, which is what I did on my old phone.
* Email works very well. I set it up to check emails from my work, Gmail, and Yahoo. I was able to stay on top of over 150 work emails during my vacation with minimal effort. This was very handy, and something I could never do with my Clie, since stylus-input is so slow (see below).
* The calendar on the iPhone will be ok, I think, but I'm definitely going to miss DB5. I have one meeting that is on the 2nd and 4th Tuesdays of the month. This is very easy in DB5, but hard on the iphone calendar. I basically had to do an every 2-week repeat and then adjust the months with 5 Tuesdays, since 2 every-month appointments (which is what I use in DB5) are chosen based on the numeric date, not the day of the week. That said, even though some situations like that will be a little annoying, for the majority of my appointments, this calendar will work just fine.
* The alarm clock on the iPhone is pretty good, and will completely replace Clock+ for me.
* Someone in another thread on here said that the finger-tapping that the iPhone requires would never work for him, because a stylus can hit a much smaller area (and this the GUI can be designed for that). However, this is really a non-issue. All the built-in apps handle this fine, with buttons nicely spaced on the screen. On web pages, the multi-tap zooming method is so fast, so if something is too small to tap with your finger, you just zoom in, taking less than a second, then you hit the now big link. Very easy. Plus very cool. With text, if you need to correct something or insert text in the middle, you simply hold your finger down on the text near the area you want to edit, and it brings up a magnifying glass for that area, allowing you to easily place the cursor where you need it. Again, very cool and so easy.
* I was also nervous about the keyboard, wondering about the tactile feedback of a virtual keyboard. The only keyboards I had experience with are on the NR/NX Clies that I owned. I really enjoyed having them, and my input was much faster than with the stylus. But, the iPhone keyboard works very well. Apple tells you to use one finger for a week, then switch to two thumbs. However, I started with two thumbs out of the gate, and it works fine. I think what slows people down is expecting every character to be perfect, so if it's not, they initially want to go back and correct it. With the auto-correction software on the iPhone, you don't need to do this. I've had words with almost no individual letters correct, yet it still knows what word I intended to type. I've had to do almost no corrections, and I can type much faster than stylus-entry and IIRC, faster even than what I could do on the NR/NX. The other cool thing about a virtual keyboard is that it's always illuminated, and different keys are shown depending on the circumstance (for example, when you enter a zip code, it shows you numbers instead of letters), which can't be done with a hard keyboard, plus, during times when you don't need a keyboard, that space is used to display something else. I'm very happy with the implementation.
* Battery life is very good. I've been heavily using Wifi/Edge, taking pictures, listening to music, watching videos, etc, and it easily lasts a whole day. After this initial period when I'm not using it as hard, I expect it to go two days between charges.
* The camera works very well. There are no user-modifiable setting, but this seems to be mainly because the software takes care of it. In low-light settings, the shutter speed is slowed down automatically. I took over 100 pics on my vacation in all sorts of settings (still, action, day, night). The good-light pics look great, and the low-light pics are acceptable. I've had a camera on my cell phone, but never one this good. Plus, it's so easy to email the pics right from the iPhone.
* Google Maps is as good as advertised, and was very handy to have on vacation. We used it several times for both directions and to find stores/restaurants.
* The iPod part really is the best iPod ever made. My 5G iPod interface looks archaic right now. Videos look and work amazing. Toggling Shuffle and Repeat modes on and off now is done by one tap on the song you're listing to, rather than having to go back to the main menu. Really, just everything works and looks great.
* There are some v1 glitches and annoyances. Sometimes, Safari gets overwhelmed, and will just send you back to the Home screen of the iPhone. The cool thing is, this doesn't require a reset or anything, and you can just go right back into Safari if you want. I also had some problems with Coverflow on the iPhone, but that was solved by removing all my music and just syncing it again (my syncs on the first day were interrupted by my impatience to actually use the thing, and I think that caused the Coverflow problems).
As for annoyances, I wish it weighed a little less and had at least 16GB of space. You can't view lyrics on the iPod part, which is the only downgrade I've noticed in that part. I wish there was a password program for the iPhone, so hopefully someone will do that as a Web 2.0 app - the Blackberry, which I also looked at, has this built-in. I wish the picture and web auto-rotate thing (which is just amazing in those apps) worked in email and for GoogleMaps.
I'm probably forgetting things, but it's late and I'm tired, and this mini-review isn't all that small anymore
Like I said earlier, if you have any questions, just ask.
All in all, I'm very pleased with the iPhone. For TH users, this is a device with a similar form factor that is actually slightly smaller and can be used as a cell phone and an iPod, with software that for the most part is an upgrade over the Clie.