Logging In
To use Comcast Mobile, you need to be a customer, preferably a "triple-play" customer with High-Speed Internet, Voice, and HD Cable. I don't use Comcast's voice service, but I do have the other two services and I still found Comcast Mobile to be useful.

Using your comcast.net email address and the password used to log into the webmail site, you enter the pertinent information into a settings page. You can choose to save your password for an instant login.

The Home Screen
The home screen for Comcast Mobile has large buttons for the five major functions; Inbox, Address Book, Digital Voice, The Guide, and One Demand. You can also access an information screen with links to an FAQ list and Getting Started Guide, a Contact and Feedback list, Discussion Forums, and the ever-popular Terms & Conditions.

The information screen was having some issues during my test; since it links to the Comcast website, it gave me a notice at one point that my browser wasn't supported. One of my complaints about the FAQ list/Getting Started Guide page was that it wasn't formatted for the iPhone or iPod touch -- it's just the regular Comcast customerCentral web page, so you need to scroll back and forth to view the information. I was a bit concerned by the "We're still working on content" filler page that was up just a few scant days before the expected release of Comcast Mobile.

The Settings screen is also accessed from the home screen, and features a number of choices for configuring your iPhone or iPod touch for optimum use of the site.

The Inbox
The unified inbox is the same inbox that Comcast customers can access online through www.comcast.net. The two inboxes, iPhone and online, are always kept in sync. While having access to voicemail and email in the same inbox might be attractive to some users, others may wish to access their Comcast email accounts from the iPhone's Mail app. Comcast could have considered using Apple's Mail app and provided a way to listen to Comcast voicemail in that app. Vonage VoIP customers, for example, can listen to their voicemail messages in the standard Mail app.

The Inbox has five separate tabs; one contains both email and voicemail, another only email, yet another only voicemail, another for folders that the user creates, and the last for searching the Inbox for specific messages. To read an email, you simply tap on it. Once you have opened an email, a series of icons at the bottom allow you to refresh the inbox, move the message to a new folder, trash it, forward or reply to it, or write a new email. In the Inbox, you can also select multiple emails for deletion.

Address Book
The Address Book in Comcast Mobile synchronizes initially with the SmartZone address book on the online Comcast site. When synced, any items in the online address book are synced to the Comcast Mobile and iPhone address books. Likewise, any contacts added to the iPhone or Comcast Mobile address books are synced to the online book.

Digital Voice
Tapping the Digital Voice button opens a completely different inbox, one that handles only calls made on Comcast's Digital Voice product. There are four tabs in this section of Comcast Mobile, one to see all phone calls made or received, one to see only outgoing phone calls, another to see missed calls, and a final tab for voicemails only.

Tapping on a voicemail plays it back. You can mark the message as unheard if you wish to be reminded to listen to it again. Voicemails appeared in Digital Voice and in the Inbox within seconds of being recorded. The Digital Voice area is also where you can set up call forwarding for your Comcast Digital Voice account. This is very useful for forwarding your account to your iPhone when you're away from home.

The Guide
I found The Guide to be the most useful section of the TV Listings. In fact, I wish that Comcast would simply use online listings such as this and get rid of the large paper guide they send to my home monthly. I usually toss it in the recycle bin anyway since it's full of gushing news about celebrities that I neither follow nor care to follow.

The first time you open The Guide, you're asked to enter your zip code. This ensures that you see the proper channel listing and times for your area. The listing is in order by station number, and shows what is currently on each station as well as what will be showing in a half-hour. To see future listings, you simply flick the listing to the left.

All shows that are on HD channels show up with a small blue HD icon next to them. Tapping any of the show listings pulls up program details. On the program details page is a button for other showtimes, and tapping on it lists all of the upcoming times that the show will be aired. You can tap a button to add a program to a list of favorites, or tap another to share an upcoming show with a friend via email.

One of my favorite features is the ability to set reminders about upcoming shows. Any show that is set in the future can be set as a reminder on the program details page. You can set an alarm to sound at showtime or at 5, 10, or 15 minutes in advance.

The search function works fairly well, although I found myself sometimes getting odd results. For example, searching for Lance Armstrong not only gave me some correct hits (e.g., "Tour de France: Astana Profile"), but some that were way off the mark (e.g., "This Girl for Hire", a movie starring Bess Armstrong, who also shows up in "Jaws 3-D"). I tried a search with the name in quotes ("lance armstrong"), but that returned no hits at all. Still, the search will always return more results than just the correct ones, so you should be able to find just about everything you're looking for.

On Demand
I'm sure that many Comcast customers were hoping that On Demand would actually provide streaming movies, but that was not to be. What it does is give you is those preview videos that are in heavy rotation on Comcast Channel 1, enticing you to watch free On Demand movies or pay for the latest releases.

The videos are formatted for the iPhone screen and both look and sound great. There's a Cover Flow-like interface for new releases at the top of the display, followed by a series of buttons leading to detailed descriptions for other movie trailers sorted by genre.

What Comcast Mobile is missing
As a Comcast customer, there are a few things that I'd like to see added to the app in future releases.

First, it would be nice to be able to go to an online customer service site formatted just for the small screen size of the iPhone and iPod touch. This could be constructed similarly to AT&T's myWireless app, which provides a mobile portal to any and all account information. You can view and pay bills from the app, and even purchase or upgrade services.

Next, I know that Comcast's existing set top boxes / DVRs probably don't handle Wi-Fi or Bluetooth connections (the one I have certainly doesn't), but it would be wonderful to have the ability to use Comcast Mobile as a remote for all things on cable. In other words, let's not just use the iPhone as a way to see what's on TV and get a reminder, but to actually control the set top box! As I noted earlier, Comcast is planning to add a way to set your DVR in the next release of Comcast Mobile.

What about streaming video from my set top box or DVR to my iPhone? I'm paying for the content, so it would be nice to use that content even when I'm not at home sitting in front of the HDTV.

Finally, since the online Address Book has the ability to let you send ecards to people in your list, why not add that function to Comcast Mobile?

Summary
All in all, Comcast Mobile 1.0 is a surprisingly useful and fun app for the iPhone and iPod touch. I don't watch much TV, but I found myself using The Guide to find out what was coming up on my Comcast digital cable. I personally wish the Comcast digital cable on-screen guide was as easy to use as the one found in Comcast Mobile.

Comcast has done a wonderful job of taking the functions built into their Digital Cable, High-Speed Internet, and Digital Voice offerings, and tailoring them to the multi-touch interface of the iPhone and iPod touch. I look forward to using both this initial offering and future updates to Comcast Mobile. Now if they could only work with Apple to transform the AppleTV into a much better "cable box" and media center...

Be sure to check out screenshots of Comcast Mobile in action: