Comcast has just jumped on the iPhone bandwagon with the “Comcast Mobile App” — now available for free download from the iTunes App Store.

The program gives Comcast subscribers access to Digital Voice features such as voicemail, contact management (you can sync your iPhone contacts with your Comcast contacts), and call forwarding from your home phone to your iPhone. You also have access to your Comcast e-mail with both e-mail messages and voicemail messages under one “SmartZone” tab.

As for TV features, there’s a built-in TV guide feature that allows you to favorite certain shows and e-mail them to friends. It works well but the lack of a remote DVR feature a la TiVo is a painful omission — both for Comcast in general and for this app. It’d be great to cruise the TV guide and just click a “record this show” button to have it waiting for you when you get home. I suppose you can’t quite fault the app for not having that feature since Comcast doesn’t offer it in any form to begin with.

The OnDemand feature, too, would be awesome if it could stream full OnDemand programs. Instead, you’ve got access to trailers for movies that are available on your home cable box. There’d be some serious bandwidth issues with OnDemand streaming of full movies and TV shows but the feature could be implemented by using an “only over Wi-Fi rule” perhaps.

And, of course, that’s not to say that features like full streaming and remote DVR scheduling aren’t coming someday. As it stands, Comcast’s iPhone application is a good, solid offering that’s a no-brainer for iPhone owners who subscribe to and use Comcast’s voice, internet, and cable services.

Here’s a quick video demo:

Available now as a free download from iTunes.

Comcast Mobile App [iTunes Link]