Hello, I am working on a smartphone application that will require a backend web service - but I have absolutely clueless to how much it will cost. Web Service will handle: - login of users - cataloging of our user base - holding minimal profile information for users (the only binary data is a display picture which will be < 20k each) - performing some very minor calculation/algorithm before return results - All the above will be communicated to server from a smartphone (iPhone/BlackBerry/Android) Bandwidth Requirements: - We want to handle up to 10k users throughout the day. - I predict 10k * 50 HTTP requests a day = 500,000 requests a day * 30 = 15 million requests a month Space Requirements: - Data will be in SQL database. - I predict 1MB/user * 10k = 10GB + overhead. In other words - space is not a big issue. Software Requirements: (unless someone knows an alternative) - Windows Server 2008 + IIS - MSFT SQL Server Note: This is 100% new to me, so please hit me with all you got. Do I need Windows Server or are there alternative? Is it better to get multiple cheap servers to distribute load? Will Amazon S3 work for me? How about Windows Azure? Thank you!!