A new application to be available within several weeks will also let customers manage their Rackspace cloud accounts from their iPhones, the company says.

The API itself was developed for Cloud Servers, which gives customers access to virtualized server instances, and closes a gap with Amazon's Elastic Compute Cloud just as Rackspace is trying to repair its credibility in the wake of recent

The API lets customers create, configure and control virtual servers within the company's cloud computing platform. Rackspace says. For example, the API "enables elastic scenarios as users can write code that programmatically detects load and scales the number of server instances up and down."

A Rackspace partner called Cloudkick has developed an application that allows workloads to be moved back and forth between Amazon EC2 and Rackspace Cloud Servers, according to Emil Sayegh, Rackspace's cloud general manager. The ability to move workloads is a key goal for ensuring among cloud platforms.

"What the API allows you to do is open up the systems to each other," Sayegh says. "Cloudkick … wrote an application that moves an EC2 instance to a Cloud Server [and vice versa]."