I have both a. iPhone 4 and a Samsung Captivate...here are my thoughts I just posted on another forum...
I have both phones as well and for the most part agree with what you said with a few more thoughts.
The Captivate works much better as a PHONE while the iPhone works much better at everything else so it depends on what is more of a priority for you.
As a phone, I find the Captivate more natural to hold, it has a signal everywhere for me and not one dropped call in the past week. The iPhone would drop at least a call or two per day. Captivate also works better over Bluetooth car handsfree and has useful basic features like long press speed dial and searching using the numerical keypad. One place the iPhone does much better is Visual Voicemail. I have Google Voice setup for Visual Voicemail on the Captivate but it's buggy at times. The volume is real low for some reason and sometimes it takes a while to load the messages, I've even had it give me an error that it couldn't connect. Never ever had a problem with Visual Voicemail on the iPhone.
The Captivate does a much better job for settings and switching different things on/off via widgets, but that can be done an a jail broken iPhone as well.
Typing is much better on the Captivate because of Swype. I love it.
For me, that is where the advantages of the Captivate stop.
The display is a hands down winner for the iPhone for me. I know the screen is smaller but it more than makes up for it with the clarity. Items on the Captivate look jagged...not always but often enough.
Email on the iPhone works much more reliable for me. I have it setup as IMAP and it just works, never had an issue syncing. On the Captivate, I've tried the stock app, K-9 and MailDroid and none have been reliable. Even Gmail, which gets the email real quick...doesn't work properly with my Apple Mail program (shows messages still haven't been read even though they were read on the Captivate). Visually the iPhone mail app is much more polished than anything available on the Android Market.
Browser is not as good on the Captivate, and I tried Dolphin HD too. Just usnt as smooth and I don't like how it renders the text.
Text messaging is pretty similar with using ChompSMS on the Captivate but again the iPhone is more polished when adding a picture to your message or allowing you to call the person directly from within the app.
The camera is far superior on the iPhone. I did some tests of shooting the same scenes and the iPhone easily won. Much sharper and better color photos. The app itself is also easier to use. Yes the iPhone has almost no adjustable features but it doesn't need them here, it just works well the way it comes. The LED flash is also great, not only for pictures but also as a flashlight.
Android Market vs App Store again is no contest. The App Store just has a lot more mainstream support. I couldn't find any apps to play Romanian radio on Android whereas the App Store has dozens of them. There is no Chase Banking app on the Android market and before you say there are alternatives, they are not close enough. The iPhone app allows me to deposit checks by taking a picture of the, the Android copy, not so much. These are just a couple examples but you get the idea.
That about wraps it up. As you can see, my biggest gripes withnthe Captivate are mostly Android related. It just feels amateurish to me, like a bunch of "shade tree" developers put it together while iOS feels like it was put together by a company who knew and cared what it was doing. I know youncan customize it as you want but Ive been trying for the last week to find the correct apps to make it "just work" and haven't been able to yet.
It's funny, I usuallybhave both phones within reach and I grab the Captivate if I need to make a call and the iPhone for everything else. I still haven't decided which I'm going to keep...having a cell phone that actually works as a phone is a pretty high priority.
