From Gambit wiki
Gambit REPL is an app based on the Gambit Scheme system which is available for mobile devices such as the iPhone and iPad. It provides a REPL to interact with the interpreter, a script editor, and builtin documentation. Scripts are stored locally on the device, and it is possible to share scripts by uploading them to the public script repository, which is the Gambit wiki itself (allowing anyone to view the scripts using a web browser, whether they are users of Gambit REPL or not).
The documentation for Gambit REPL is available in the "Help" view of the app. This page of the Gambit wiki is for user contributed comments and documentation which are of general interest to the Gambit REPL users. Please contribute!
The list of scripts uploaded to the public script repository is available here.