Mobile deathmatch: Windows Phone 7 vs. Apple iPhone 4
Microsoft has a very slick device, but it can't do nearly as much as the iPhone -- especially in businessFollow @MobileGalen
Both the iPhone and Windows Phone 7 remember the email addresses of senders you reply to, adding them to a database of contacts that it looks up automatically as you tap characters into the To and Cc fields. Both devices let you add email addresses to your contacts list, either by tapping them (on the iPhone) or tapping and holding them (in Windows Phone 7).
Contacts and calendars. The iPhone 4's more stylish UI for email applies to its Contacts and Calendar apps as well. Both the iPhone and Windows Phone 7 offer the same views: list, day, and month. The iPhone's calendar is easier to navigate, with better indicators of days that have appointments in the month view; Windows Phone 7's list view is too spare, so you lose differentiation among objects, and its month view makes it hard to see which days have appointments.
You can easily switch calendar views in the iPhone 4 in the main calendar screen; Windows Phone 7 also makes switching easy, both through swipes and through its button row at the bottom of the screen. Both can display multiple calendars simultaneously.
On the iPhone, your invitations for Exchange accounts show up in your calendar so that you can accept them with the full context of your other appointments. For other email accounts, you're stuck; it doesn't let you open the .ics invitation files in Mail, nor does Calendar detect them. As Windows Phone 7 won't work with my corporate Exchange server, I can't say how it handles Exchange calendar invites. For other accounts, Windows Phone 7 lets you accept invitations by tapping a menu in your message. You can even send a proposed alternative time and date.
Windows Phone 7 lets you issue invitations from its calendar; the iPhone can issue invitations only for Exchange calendars, not Google ones. Note that Windows Phone 7 doesn't send the invites immediately, so it's not so good for planning an urgent meeting. But Windows Phone 7 has a nice feature: You can tap a button that composes an "I'm running late" email addressed to the meeting's attendees.
Both the iPhone and Windows Phone 7 have capable Contacts apps, but the iPhone 4 makes it easier to navigate through your entries. You can jump to names by tapping a letter at the side of the screen, such as "t" to get to people whose last names begin with "t," or seek quickly for someone in the Search field by typing in part of the name. In Windows Phone 7, you have only the search capability to find contacts; there's no quick-jump function.
Windows Phone 7 lets you designate users as favorites, to put them in the Home screen. The iPhone 4 has no equivalent. And Windows Phone 7 lets you link contacts, so you can see all their information in one place, such as personal and business entries for the same person, or separate entries for family members. The iPhone supports email groups, but you can't create them on the iPhone; they must be synced from your computer's contacts application. Windows Phone 7 has no group list capability.
The winner: The iPhone, thanks to its support of critical Exchange ActiveSync policies. If you don't use Exchange, the two mobile OSes are fairly equivalent. The iPhone is slightly better in its email handling, but Windows Phone 7 is better for calendars. Contacts management is a draw.
The iPhone provides more useful apps than Windows Phone 7 does. Both provide email, contacts, calendar, browser, calculator (except on the iPad), maps, a music player, photo display, a video player, multi-user gaming, weather (buried in the Daily Briefing app on Windows Phone 7), and SMS messaging apps. The apps are equivalent in most cases. One exception is the photos app, where the iPhone supports albums and Windows Phone 7 does not. Another exception is the maps app, where the iPhone provides satellite views in addition to cartographic ones; the iPhone's maps app is also much faster at returning directions.
The iPhone provides several apps that Windows Phone 7 does not, including those for the weather, stocks, voice memo, and YouTube. Although Windows Phone 7 supports an alarm app and some clock display features in its Daily Briefing app, it offers only a subset of what the iPhone's clock app does.
[Updated 11/19/20]Windows Phone 7 has a set of apps called Office: Word, Excel, and OneNote. But don't let the Office name fool you -- Word and OneNote are very rudimentary apps, good for basic notes entry and extremely light editing. For example, tap and hold a word to select it or tap and drag to select a range of text; from there, you can make it bold, apply a colored highlight to it, or add a note. You can't choose fonts, though you can apply numbered and bulleted lists. Note that when I tested mobile Office using a Samsung Focus, I could select only one word at a time, no matter how hard I tried to select more. I assumed that was a limitation in mobile Office, but later testing on an HTC Surround shows the text selection works quite easily on that device. It's unclear why I could not select more than a word at a time on the Focus, though a possible cause could be its touchscreen, which was less sensitive than other smartphones I have used.
Excel likewise is good only for very basic editing; constructing formulas is very difficult, as you can't tap a cell to enter it into a formula. You can tap the fx icon to get a list of formulas, as in the desktop version, but the default keyboard for Excel doesn't display two of the most common symbols used in formulas: = and *; you have to switch to a second symbols keyboard.