Technology giant Apple’s one-stop cloud-based photo, video, music and data back up and push out service iCloud has generated a lot of interest and Apple has even held back the launch of its new MacBook Air and other products so that it could bundle iCloud with all future product launches. But does iCloud have what it takes to beat Google Music Beta digital locker, Amazon Cloud Drive, Microsoft Sky Drive?

iCloud is one of Apple’s most ambitious service offerings ever. No wonder at World Wide Developers Conference (WWDC) 2011, Jobs himself took the stage to speak about iCloud. I get to talk about iCloud, the tech guru said.

Jobs began his presentation on iCloud by grumbling how advancements in digital technology have made it difficult to keep various devices synced. Keeping these devices in sync is driving us crazy, Jobs said.

Stressing the importance of cloud computing, Jobs introduced iCloud. Some people think a cloud is just a hard disk in the sky, Jobs said. We think it's way more than that.

What can be stored in iCloud? Practically everything that is digital. In iCloud, one can store contacts, calendars, mail and documents. One can also store music, photos, videos, apps, and e-books (iBooks).

Apple said iCloud automatically backs up everything and can push them out to all Apple devices owned by the user. It just works, Jobs said.

The crowd went bananas when Jobs said iCloud can be a storage for APIs.

iCloud Jobs said, means the end of file storage system. Jobs said iCloud is going to be pretty big as everything is now automatic, seamless and effortless.

A significant new component of iCloud is the App Store. Once the user logs in with Apple ID and password, the user will be able to see purchase history of apps across all Apple devices. Users will also be able to buy apps, back them up and push them out to any or all Apple devices.

Like the App Store, iTunes is also now in iCloud. Which means any music or movie purchased is automatically backed up in iCloud and can be accessed using any Apple devices.

The best feature of iCloud is probably iMatch, Jobs said. For just a flat $24.99 annual fee, iMatch will match the ripped songs of the user with 18 million+ songs in iTunes and upgrade them to higher quality 256kbps AAC DRM-free.

The remaining songs that could not be matched has to be uploaded manually. First time we've seen this in the music industry, Jobs said. If you don't think we're serious about this, you're wrong.

iCloud will be free for Apple fans up to 5 GB storage.

To access iCloud, all the user needs to do is type in his Apple user ID and password. iCloud is on by default but it can be disabled.

However, there’s a downside to iCloud. iCloud can only offer limited storage days – 30 days. iCloud doesn't act as your warehouse. It can't also save all your data. But it does make sure that everything is synced and backed up properly as promised.

Meanwhile, iCloud is not alone in the cloud business.

Amazon Cloud Drive - Market leader Amazon has been in the cloud business ince 2006. Cloud Drive allows users to store their music, videos, photos and documents online and access them from anywhere they want.

The Amazon Cloud Drive offers 5 GB online storage for free if you have an Amazon accoumt. But if you think you need some more storage space, there are paid plans for storage up to 1,000 GB, with $1 for every 1 GB.

Amazon Cloud Drive also gives you the option to automatically save your purchases to your Cloud Drive whenever you buy any digital download from the Amazon MP3 Store. Thus, all your purchases will be available for you to download anywhere, anytime. A word of warning though - you can access the files from any device as long as they support Flash. It means Cloud Drive is useless for any iPhone or iPad customer since they do not support Flash.

Windows Live SkyDrive - Essentially a file hosting service, SkyDrive allows you to upload files to a cloud storage and access them from a Web browser. You need to have a Windows Live ID to keep your files private, whereas publicly-shared files don't require any such ID to access.

Compared to other cloud storage services, SkyDrive provides a lot of free storage space. The basic free account offers up to 25 GB of space. You can use 5 GB of that in conjunction with the free Windows Live Mesh application to synchronize your files across devices.

SkyDrive's interesting features include Windows Live Photos, to upload and share photos, and Windows Live Office, which offers online versions of Word, Excel, PowerPoint and OneNote. It also integrates with Bing's Save & Share feature, which allows you to save search histories into a SkyDrive folder.

SkyDrive has one limitation, however - you get 25 GB free, and that's all you can have. No options to expand.

Google Music Beta digital locker - Google's new Music Beta digital locker is a cloud-based solution that allows users to store and stream digital music collections. unlike Amazon's Cloud Drive, which allows the user to save 1,000 tracks, Google’s service supports the storage of up to 20,000 songs. The service supports Windows and Mac and comes with web-based music manager, which will not only help the user organize and play the songs but also make the songs available on all devices.

Music Beta is available initially by invitation only, and it is free — or at least so during the beta period. Music Beta is only a part of Google's cloud suite and there's no one-stop destination that hosts all your media. You have to go to Picasa to deal with your photos, Gmail for your e-mail, Music Beta for online music storage and Google Docs for your documents. Each service offers at least 1 GB of free space and if you need more, you can pay an extra $5 per year to add 20 GB for most of its services. You can also rent up to 16 TB each year for $4,000.

So what makes Apple's iCloud different from others? There are several reasons actually and each one of them, by itself is good enough to make one choose iCloud over other cloud-based services:

[1] iCloud offers accessibility of data from iOS devices, Mac and even Windows PCs.

[2] iCloud keeps back-ups of your files daily over WiFi and offers mail, calendar and contact synchronization with the cloud.

[3] iCloud automatically stores content in cloud and wirelessly pushes them out to all devices. In other words, it will automatically scan a user's library and make mirror copies available instantly on the cloud.

[4] iCloud comes with iMatch, which allows user to upgrade ripped songs to higher quality 256kbps AAC DRM-free for just a flat $24.99 annual fee.

Furthermore, Apple has stolen a march over its rivals by inking licensing deals with major music labels like EMI, Universal Music Group, Sony Music and Warner Music Group even
as Google and Amazon struggle to come to an agreement with them.

However, there’s a downside to iCloud too. iCloud can only offer limited storage days – 30 days. iCloud also doesn't act as your warehouse - it can't save all your data. But it does make sure that everything is synced and backed up properly as promised.

What do you think, is iCloud better than the other three cloud-based services? Leave your comments below.