Helping to manage my amazon ec2 servers on my ipad
I've used Cloud Services Manager to monitor and control my EC2, EBS and S3 instances and storage. Works okay. I wouldn't say it was wonderful, but it'll do in a pinch. If you're used to Elastic Fox you may find it a bit disappointing. Not quite as nice as EF.

More often than not I just use Panic's Prompt ssh client for iOS. It's quite good as ssh clients go and I'll use it to gain access to a known-good instance from which I can then run my own boto-enabled inspection tools or any of the standard EC2 command line utilities.

Between those two I can usually handle most of my EC2 issues from an iOS device.