Coda is a combination text editor and FTP client for iPhone and iPad. It is much needed utility for those that want to use the small mobile form factor of an iPhone or iPad for more than just consuming info.
With Coda you can create and modify code. After configuring it, Coda's main display shows all sites that you have set it to use, so you can easily modify entire websites by tapping on a thumbnail. Code syntax highlighting supports most every code language.
The file manager capability supports most everything you would expect an FTP client to do, including work with protocols for FTP, SFTP, FTP with Implicit SSL, TSL/SSL as well as WebDAV and WebDAV with HTTPS. It can also be used with services like Amazon's S3.
We found the iPhone app to be ok to work with, it is very powerful, but it is not going to be the tool of choice for really creating code or managing sites due to screen size and keyboard limitations. However, the iPad version, which of course you can use with a bluetooth keyboard, overcomes those limitations.
To download see: Coda in the App Store