Amazon is adding new support options for its hosted "cloud" computing services, a move that could make them more attractive for running business applications.

Amazon introduced two premium support options on Thursday for users of its EC2, S3 and SQS services. Both options guarantee subscribers a response within an hour, allow them to open an unlimited number of support incidents and provide diagnostic tools to help identify the sources of problems. They also provide an online tool where customers can view all of their open and resolved cases.

The more expensive Gold plan includes support at any time of day, 365 days a year, including live telephone support. Gold subscribers pay $400 a month or a sliding-fee scale based on usage, whichever is greater. The Silver plan costs $100 a month or $0.10 per dollar of monthly service usage, whichever is greater.

Amazon Web Services are hosted computing services that customers pay for based on usage, so they don't have to invest a potentially large sum to buy and manage their own hardware and software. EC2, or the Elastic Compute Cloud, offers remote computing power, while S3, or the Simple Storage Service, lets customers store and retrieve essentially any amount of data online. SQS, or the Simple Queue Service, is a developer tool for storing messages sent between computers.

When the services first launched, customer support consisted of an online forum that Amazon staff took turns monitoring in part-time shifts, according to a blog post announcing the new support programs. Later, dedicated workers monitored the site. But some customers are using the services for critical applications and have asked for more direct and discreet ways to seek help when issues come up, Amazon said, so it decided to offer the new plans.

Amazon also launched a new Web page that displays the health of each of the services. It lists the current status and will include historical data for 35 days, although for now the data goes back only to April 14. If a service has a problem, users can report an issue and find information on the site about the status of the problem.

The new support options should help to address complaints that customers had during two recent service outages. During the first in particular, some users were upset at the lack of information from Amazon about the cause of the problem and when it might be fixed. Some suggested in the forum that Amazon create a Web page where customers could visit to find out about service problems.

While some businesses already depend on Amazon Web Services, others may be wary about their reliability. Phil Shih, an analyst with Tier 1 Research, a division of The 451 Group, said recently that he doesn't recommend companies use AWS for anything but internal projects that can absorb downtime. However, he expects Amazon will improve the services so that in the future, he may recommend that companies use them for more critical applications.