FileMaker Pro squeezes onto an iPhone
Works better on iPad, though
FileMaker Pro, the Mac's answer to Microsoft Access, is now available for iOS – allowing the iPhone and iPad into the enterprise, as long as the enterprise is using FileMaker.
To be fair, FileMaker Pro is now available for Windows too, but with its Claris heritage it's hard not to think of it as a Mac product first and foremost. However, now we have "FileMaker Go" putting FileMaker onto iOS devices too – in client form at least.
No one's going to be creating databases, or even forms, on the £11.99 iPhone version, or even the £23.99 iPad incarnation, but users can access those forms offline by loading them over iTunes or downloading databases via email or the web (probably best to use Wi-Fi for that).
When online the client apps will connect to FileMaker Server or Pro, and support most of the desktop's functionality including the majority of scripts.
The iPhone version needs iOS 4, the iPad version obviously runs on iOS 3.2 (the iPad still awaiting an iOS 4 update). Both applications are available from the iTunes store via the FileMaker site, which also provides suitably gushing reviews from satisfied users. ®