This app will allow you to use an iPhone or iPod Touch as a keyboard, to input text on a Newton running Newton OS 2.0 or later. You will also need an adapter to connect both devices together.
See it in action on this video:
You can find the schematics for them here: iPhone Serial Port
You can find Newton Keyboard in the namedfork.net repository in Cydia.
- You can check out the source code from subversion:
svn checkout svn:/