Google looks to do for the ‘cloud’ what Apple successfully did for the mobile world by setting up a Cloud-based app store. But that could be easier said than done.

For third-party apps to successfully proliferate in this environment they will first have be integrated with existing Google Apps. The Google Apps Marketplace is an online store where Google Apps users can browse different cloud-based applications and select from a suite of online tools.

The ability to share data between existing apps like Gmail and Docs, with the new range of third-party apps expected to appear, will be an essential component. The objective is to allow individuals and enterprizes to build their own web-based productivity suites.

The store has launched with 50 apps which are logically skewed towards the business and education customers, considering they make up the vast majority of hosted Google Apps users right now. Popular areas like project management, customer retention and administration are targeted, but team collaboration should be where the cloud apps shine.

By using various Google Apps APIs and using the Google Data protocol, information can be easily accessed and moved between applications. One wonders if this may not raise further concerns around security.

And not be outdone, Microsoft has announced its plans for Windows Azure AppFabric, a set of services for building composite applications. Windows Azure AppFabric, is what enables customers to tie together their on-premise and cloud-hosted versions of Microsoft and third-party applications and products.

Microsoft plans to start billing its Windows Azure users for any applications that make use of AppFabric from April 9 and has released a pricing and billing preview for the AppFabric technology, providing developers and customers with the same kind of daily use summary they get for Windows Azure and SQL Azure.

Both Google and Microsoft are making development kits freely available to apps developers in the hope of stimulating an ecosystem emulating Apple’s success in the mobile space. It is certainly the right move and will accelerate take-up of cloud services. Only time will tell if the market feels confident enough to take advantage of the offerings. Latest reports indicate that a large percentage of enterprizes still lack the confidence to move to the cloud environment. Nevertheless, the seamless simplicity of accessing some world class applications may just be enough to overcome this nervousness.