I've been in love with the polish and responsiveness of the iPhone UI from day one. It's an awesome device for most purposes. However, from my standpoint as an experienced Microsoft Exchange Server administrator and Windows Mobile device wrangler, I'd say there are still a lot of missing pieces and things that are poorly implemented on the iPhone 3G. Given the popularity of Windows Mobile devices, I was surprised by some of the omissions and design choices Apple made for the Exchange-aware version of the iPhone.
Let's start with email, which seems like an easy enough application to implement. Apple got the single biggest item right: Push email works properly. Mail arrives when it's supposed to, and replies are sent like they're supposed to be. HTML mail displays beautifully. In fact, the overall Mail experience is basically just like it was in the original iPhone release, for better or worse. Which means that there are some problems lurking.
For example, you might think that the iPhone would work well as an offline mail client. You might also think that you should be dating Danica Patrick and that gas should be $1.25 per gallon. Bad news: None of these thoughts represent reality. The iPhone's offline behavior is poor. When the iPhone is offline, any attempt to move or delete messages results in an error dialog box. How lame is that? Did anyone at Apple test a Windows Mobile device to see how it works in such situations? At least the software is smart enough to automatically attempt a sync as soon as the network comes back up.
There are several other Windows Mobile 6 features missing here. For instance, you can't flag or unflag messages for follow-up; you can't set out of office messages or timings, and the device frequently complains if you try to throw away a message that a client- or server-side junk filter has already moved elsewhere. The extremely convenient press-and-hold shortcuts that Windows Mobile provides (such as "d" to delete or "m" for move) are, of course, absent here, too, because they depend on having a physical keyboard.
Bottom line: Mail is prettier on the iPhone than on Windows Mobile devices. I think the iPhone and Windows Mobile 6.1 devices are tied in terms of sync behavior and sync performance (subject to cell coverage and bandwidth availability). My Windows Mobile 6.1 device has a significant edge in speed because I can navigate through, read, move, and triage messages with one hand, and I can use the press-and-hold keys. For novice users, this speed differential might be much smaller . . . but I'm not a novice. And, to forestall any flames: The iPhone keyboard is OK with me. After I got used to it, it's as fast as a physical keyboard.
As for features other than email, those are a mixed bag too. Calendaring has some major omissions; for example, you can't invite people to events you create on your own calendar! You also can't create items in a different time zone than the one you're in. Apple's Notes application is terribly lame, and it doesn't sync with Exchange at all—nor does it sync with a Mac or Windows machine through iTunes! There's no tasks/to-do application at all, another major omission.
I didn't have space in this column to fully chronicle all the bugs, glitches, and missing features in Apple's "enterprise" iPhone software; for that, you'll need to see my blog. For now, I'm sticking with an iPhone for play and my Windows Mobile device for actually getting work done.