Subscribers to Apple's $99 a year MobileMe service (even cheaper from Amazon
Launch the app and you will be prompted to provide your MobileMe username and password. You will then see a list of all of your MobileMe folders.
Tap on a folder and you will see a list of the files in the folder. Tap on a file supported by the iPhone such as a Word or Excel document, an iWork document, a picture, a video or a song, and the file will be downloaded from your iDisk to your iPhone so that you can view the file. You can quickly see a list of files that you have recently viewed by tapping on the Recents icon at the bottom. In the Settings, you can decide how much space to devote to iDisk files that you download (the default is 100MB) so that when you return to a file that you recently viewed, the file pops up instantly without having to download it again. In addition to viewing files on your own iDisk, you can tap on the Public Folders icon to view the public files of other MobileMe users.
Viewing files works great, and while there are other apps that currently allow you to do the same thing (such as Quickoffice) it is nice to have a free app from Apple. But what makes the iDisk app really powerful is the ability to share files on your iDisk, especially larger files that would be a hassle to attach to an e-mail. I'll walk you through an example to show you how it works.
In my Music folder I have two songs that my father (an architect by day and amateur musician by night) wrote. Let's say I am out and about and I want to send the song to a friend of mine. I have the song on my iPod, but of course you cannot e-mail files from the iPod. However, because I have a copy of the song on my iDisk, I can load up this app and tap on the share icon to the right of the song. This creates an e-mail from my MobileMe e-mail account. I choose a recipient by tapping the plus sign to choose from my address book (or just type in any e-mail address).
I now have access to the advanced MobileMe file sharing options. By default, the recipient will have one month to download the file and will not need to enter a password, but you can change those options if you want. Enter any message that you want and then hit send.
The recipient then gets an e-mail that doesn't have the file attached but instead has a button that can be clicked to download the file to their computer. It looks much like this:
Again, this is great for large files because you avoid dealing with the problems of big attachments such as slow e-mail. Once you are sharing a file, you will see an indication in the form of a green icon that the file is being shared. You can also tap on the Shared Files icon at the bottom of the screen to see all files that you are sharing. At any time, you can change the sharing status for any file by tapping the sharing icon, so you can make the file available for a longer time, or you can stop sharing the file completely.
Apple has also posted this video to show you more about the app, but I don't think you really need to read any further; if you use MobileMe, then you will want to get this free app. Not only does it give you an easy way to view your iDisk files, but it also gives you a great solution for sharing larger files, even when you are on the go and only have access to your iPhone but not your computer.
By the way, if you want to download the song I am using in my example titled "The New New Orleans," click here to download it (for free!) from my iDisk. It's a fun, toe-tapping song recorded in late 2005 which, as I mentioned in my sample e-mail, captures the positive spirit of post-Katrina New Orleans. My father Bob Richardson (who wrote the song) is on guitar, and the other great New Orleans musicians who recorded the song are Dave Carboni as lead vocal and on bass, Jason Lohmeyer on keyboard and Buzzy Beano on guitar and banjo. I'd love to hear from you if you like the song; my Dad will get a kick out of knowing that others are enjoying it.
Click here to download MobileMe iDisk (free): 
