The promise of cloud-based storage is that whenever you need a document or other item, it's wherever you are. In a perfect world, cloud storage and cloud-based synchronization prevent you from having to manage any of your media, files, programs, and other bits and pieces.

Apple's iCloud attempts to provide that. But it's not quite as seamless as the company wants it to be.

Apple announced iCloud in June and opened it for public use Oct. 12, the same day it made the iOS 5 update available to iPhone, iPod touch and iPad owners. Both Lion and iOS now have baked-in support for iCloud, which is free for up to 5 GB of storage. Apple doesn't count any purchased items (apps and media), as well as temporarily stored photos from iOS or Mac OS X, against that 5GB. The free storage can go a long way.

I offered an overview of iCloud features when it was announced (Personal Technology, July 2). Let's look at how it plays out in practice.

While iCloud works more or less as expected, the worst problem you may experience comes before you even log in. Apple biffed the issue of multiple accounts handled by one person, as well as families with multiple accounts, one to a person. iCloud only works with a single Apple ID, the unified login account for purchases, MobileMe, iChat and other purposes.

If you had a MobileMe account and you used that ID for all your purchases, you can migrate it over to iCloud and you won't have any difficulties. (MobileMe remains active until June 30, 2012, but once you transfer an account to iCloud, you can't switch back.)

But I'm like many longtime Apple product users who have accumulated accounts over time because of how Apple initially set up its stores and services. I primarily use a MobileMe account for syncing and services, like Back to My Mac, and one personal email account for purchases. Apple does allow you to retain those two identities in iOS 5, Mac OS X, and iTunes: One account can be set for iCloud and another for the various stores.

But if you have any overlap of purchases from those two accounts, you'll find yourself regularly confronting irritation.

Apple has provided no method — and has no timeline for providing a method — to merge accounts and associated purchases and purchase history. An executive decision was made many months ago to not treat this as a situation that had to be dealt with. I hope that changes.

An email from Apple to a customer after a query to Chief Executive Tim Cook indicates Apple may ultimately provide some path for account consolidation. Apple also offers no family master account to associate purchases and other items together, which again makes it difficult to share media legally in a single household.

In regular use, iCloud seems to meet most challenges. Setup is quick. You tap or type in your login name and password in Settings in iOS 5, or the iCloud preference pane (Mac) or control panel (free Windows download). Check the services you want to turn on, and you're up and running.

Syncing works perfectly fine, as did Back to My Mac for remote system access. iCloud adds Find My Mac, a new feature designed to aid with recovering a stolen or lost computer, just like Find My iPhone.

I set up iCloud-based backups for my iPhone and iPad 2, each of which have a few gigabytes of material that can't be restored from the App Store, iTunes Store, or media stored in a copy of iTunes running on a desktop computer. Apps aren't backed up, for instance, but document files are. I bumped up my iCloud storage by paying the annual $40 fee to add 20 GB. (You can add 10 GB for $20 per year or 50 GB for $100 per year instead.)

I plan to sign up for iTunes Match when it's available later this month. For $25 per year, iTunes will examine your music library and identify matches in its large music catalog. Any matching music is provided at full 256 Kbps AAC quality, while Apple uploads any non-matching songs. This makes your entire iTunes library available anywhere. Matching songs aren't counted against iCloud storage, but your unique music is.

I was able to test the iCloud backups with a new iPhone 4S. After backing up my iPhone 4 and confirming a recent backup was in place, I activated the iPhone 4S and chose to restore it. This came with some glitches that I can save you trouble in avoiding.

If you perform an iCloud restore, iOS 5 wants to restore everything via the Internet. For me, this included about 15 GB of apps, music and other files in Apple's various stores.

While the restoration was under way and the phone was usable, I plugged my iPhone in to iTunes, and enabled Wi-Fi Sync. This features allows a copy of iTunes on your own Wi-Fi network to communicate with an iOS device without being plugged in via USB, which is an alternative. Wi-Fi Sync automatically runs when your device is connected to a power source, or you can trigger it manually.

Unfortunately, running Wi-Fi Sync and iCloud restore at the same time lost all my app screen placement and folder organization, and caused the Music app to have unplayable tracks, some of them grayed out. After trying a variety of solutions, I wiped the phone and left it to restore from iCloud overnight.

Despite that, music syncing wouldn't complete after many tries until the problem disappeared without additional intervention. My iPhone told me to look to iTunes for errors, which displayed none.

One would think Apple would have considered a conflict between Wi-Fi Sync and iCloud restore, and have given one priority over the other. Or offered the option to restore apps and purchased music (without losing folders and screens) directly from iTunes to reduce time and bandwidth consumed. More and better interaction needs to be put in place.

I have high hopes for the dust settling around iCloud. For backups and syncing, the service so far works great. The addition of Find My Mac and Back to My Mac at no cost are great benefits.

But Apple needs to focus a bit more of its attention, and make iCloud less of a struggle to manage across accounts and with restores.

Glenn Fleishman writes the Practical Mac column for Personal Technology and about technology in general for The Seattle Times and other publications. Send questions to gfleishman@seattletimes.com.

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